Summary:
This commit removes special cases for linking iOS and Android platforms.

A previous commit opened up link and other commands for other platforms to provide their own behaviors. It left special cases in tact for iOS and Android. This PR removes the special case.

- Added jest tests related to the link command.
- Ran the `link` and `unlink` commands for iOS and Android and confirmed no changes.

https://github.com/facebook/react-native/pull/17745

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  CATEGORY
[----------]        TYPE
[ CLI      ]   [-------------]      LOCATION
[ DOCS     ]   [ BREAKING    ]   [-------------]
[ GENERAL  ]   [ BUGFIX      ]   [-{Component}-]
[ INTERNAL ]   [ ENHANCEMENT ]   [ {File}      ]
[ IOS      ]   [ FEATURE     ]   [ {Directory} ]   |-----------|
[ ANDROID  ]   [ MINOR       ]   [ {Framework} ] - | {Message} |
[----------]   [-------------]   [-------------]   |-----------|

[CATEGORY] [TYPE] [LOCATION] - MESSAGE

 EXAMPLES:

 [IOS] [BREAKING] [FlatList] - Change a thing that breaks other things
 [ANDROID] [BUGFIX] [TextInput] - Did a thing to TextInput
 [CLI] [FEATURE] [local-cli/info/info.js] - CLI easier to do things with
 [DOCS] [BUGFIX] [GettingStarted.md] - Accidentally a thing/word
 [GENERAL] [ENHANCEMENT] [Yoga] - Added new yoga thing/position
 [INTERNAL] [FEATURE] [./scripts] - Added thing to script that nobody will see
-->

[CLI][FEATURE][local-cli/link/link.js] - Removes special cases for linking in iOS and Android.
Closes https://github.com/facebook/react-native/pull/17961

Differential Revision: D6975951

Pulled By: hramos

fbshipit-source-id: 8dd5da35619e2124ce4b3b18db8b694757792363

Summary:
This change adds hooks via the `package.json` for a platform plugin to specify hooks for generating platform configurations. This change also adds hooks to allow platform plugins to participate in `link` and `unlink` commands. The goal is to move platform-specific code for platform plugins into their own repositories / node_modules.

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We need to be able to configure the CLI commands for plugin platforms (e.g., react-native-windows) in their own repositories.

(Write your test plan here. If you changed any code, please provide us with clear instructions on how you verified your changes work. Bonus points for screenshots and videos!)

- All jest tests, including new tests, pass.
- `link` and `unlink` commands are successful on iOS and Android.

(If this PR adds or changes functionality, please take some time to update the docs at https://github.com/facebook/react-native-website, and link to your PR here.)

https://github.com/Microsoft/react-native-windows/pull/1601

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Help reviewers and the release process by writing your own release notes

**INTERNAL and MINOR tagged notes will not be included in the next version's final release notes.**

  CATEGORY
[----------]        TYPE
[ CLI      ]   [-------------]      LOCATION
[ DOCS     ]   [ BREAKING    ]   [-------------]
[ GENERAL  ]   [ BUGFIX      ]   [-{Component}-]
[ INTERNAL ]   [ ENHANCEMENT ]   [ {File}      ]
[ IOS      ]   [ FEATURE     ]   [ {Directory} ]   |-----------|
[ ANDROID  ]   [ MINOR       ]   [ {Framework} ] - | {Message} |
[----------]   [-------------]   [-------------]   |-----------|

[CATEGORY] [TYPE] [LOCATION] - MESSAGE

 EXAMPLES:

 [IOS] [BREAKING] [FlatList] - Change a thing that breaks other things
 [ANDROID] [BUGFIX] [TextInput] - Did a thing to TextInput
 [CLI] [FEATURE] [local-cli/info/info.js] - CLI easier to do things with
 [DOCS] [BUGFIX] [GettingStarted.md] - Accidentally a thing/word
 [GENERAL] [ENHANCEMENT] [Yoga] - Added new yoga thing/position
 [INTERNAL] [FEATURE] [./scripts] - Added thing to script that nobody will see
-->

[CLI][FEATURE][local-cli/core/index.js] - Allow platform plugins to contribute to the RNConfig.
[CLI][FEATURE][local-cli/link/link.js] - Allow platform plugins to participate in the `link` command.
[CLI][FEATURE][local-cli/link/unlink.js] - Allow platform plugins to participate in the `unlink` command.
Closes https://github.com/facebook/react-native/pull/17745

Differential Revision: D6883558

Pulled By: hramos

fbshipit-source-id: ea32fe21cedd4cc02c5c0d48229f2cdb2ac8142b

Reviewed By: emilsjolander

Differential Revision: D6675111

fbshipit-source-id: 884659fabb05033b4d43d3aa6629e22481d39b7e

This reverts commit f6f8d7b1.

Reviewed By: emilsjolander

Differential Revision: D6675111

fbshipit-source-id: 884659fabb05033b4d43d3aa6629e22481d39b7e

Summary:
The code to display HMR errors on the client was reading the `description` field from Metro payloads. Metro does not include `description` in the body of its error payloads -- only in its `body.errors[]` items. This commit changes RN's HMR code to show `body.message` (set consistently with https://github.com/facebook/metro/pull/124) instead of the non-existent `body.description`.

Open a test RN app, enable HMR, and then introduce a syntax error in an app source file. See that the redbox provides information about the syntax error instead of just saying "TransformError undefined".

- https://github.com/facebook/metro/pull/124

[GENERAL][ENHANCEMENT][HMR] - Fix display of syntax error messages when HMR is enabled
Closes https://github.com/facebook/react-native/pull/17619

Differential Revision: D6726516

Pulled By: mjesun

fbshipit-source-id: b1d1008d6f1aa8f88ff8a2aa1374724a305c773b

Summary:
Fix issue #17027 (`RCTModalHostView` has a tvOS dependency that was not wrapped in `TARGET_OS_TV`)

Existing test automation should pass.

[GENERAL] [BUGFIX] [tvOS] Fix cocoapods compile issue in RCTModalHostView
Closes https://github.com/facebook/react-native/pull/17502

Differential Revision: D6688166

Pulled By: hramos

fbshipit-source-id: 38297f439f75a8303f59f83b92e004c6c73d9bf6

This reverts commit 9f33fe25.

This has been recently added to Node 8.x. Since it makes our tests to fail, I decided to
do a workaround that works for all the versions.

This reverts commit 71006f74.

Define missing "beforeEach" so that Flow does not complain.

Facebook is probably having these defined in another manner which
makes their internal test suite pass.

This reverts commit dd016f33.

Define missing "before" function so that it does not cause flow
to fail.

Reviewed By: TheSavior

Differential Revision: D6576053

fbshipit-source-id: d727811f7bfdb5cb9a0da010ee0c225029b18b26

Summary:
Fix typo in RCTSurfaceHostingView (minumumSize -> minimumSize)
Closes https://github.com/facebook/react-native/pull/17235

Differential Revision: D6585719

Pulled By: hramos

fbshipit-source-id: bfb18015f48bc8ab161945d09125c27d29738ede

Summary:
This is a long story. Awhile ago awesome Nick Lockwood (Hey Nick!) introduced a special optimization for ReactNative rendering layer called "inherited background color".
He described this idea in D2811031:
>>>
Blending semitransparent pixels against their background is fairly a fairly expensive operation on mobile GPUs. To reduce blending, React Native has a system called "background color propagation", where the background color of parent views is automatically inherited by child views unless explicitly overridden. This means that translucent pixels can be blended directly against a known background color, avoiding the need to do this dynamically on the GPU.
In practice, this is only useful for views that do their own drawing, which is basically just <Image/> and <Text/> components, and for image components it only really matters when the image has an alpha component.
The automatic background propagation is a bit of a hack, and often does the wrong thing - for example if a view overflows its bounds, or if it overlaps a sibling, the background color will often be incorrect and need to be manually disabled. Because the only place that it provides a significant performance benefit is for text, this diff disables the behavior for everything except <Text/> nodes. It might still be useful for <Image/> nodes too, but looking through the examples in UIExplorer, the number of places where it does the wrong thing for images outnumbers the cases where it provides significant reduction in blending.

However. I think it is time to remove it. Why? There are several reasons:

* It drastically complicates rendering layer. DRASTICALLY. In many many unrelated places (try search for "backgroundColor"!);
* This mechanism is totally non-conceptual to RN and it prevents us to implement some new possible render optimization that we plan to do;
* This adopted only by two components now: Text and ART;
* This is not a significant performance drain anymore; from iOS 6 even UILabel has clear background color by default.
* I doubt that it even works now because `drawRect:` in Text component does not call super method.

So, this diff just turns this feature off for Text. If all performance metrics are neutral, I will delete this mechanism.
Peace.

Reviewed By: sahrens

Differential Revision: D6564199

fbshipit-source-id: 70524fdd955ca32bbf86d2d1ff5e73316b791219

Reviewed By: rafeca

Differential Revision: D6579060

fbshipit-source-id: f36a87bce9633370a02b8991cec4aced05ca72d1

Reviewed By: rafeca

Differential Revision: D6578653

fbshipit-source-id: 99ec17bcb7c1f4daeb868c3755a9e6e668d1ae61

Reviewed By: pakoito

Differential Revision: D6531199

fbshipit-source-id: ed1ae9e2f0c19e7656cd022e438693798320e55a

Reviewed By: rafeca

Differential Revision: D6578053

fbshipit-source-id: b9d4e2e5820854ffe0e9cb54a78436d0ef2917ce

Reviewed By: rafeca

Differential Revision: D6555773

fbshipit-source-id: 9d10a3d03c88eeaa2d6845518da3dacab8b556b0

Reviewed By: rafeca

Differential Revision: D6532920

fbshipit-source-id: d1463aa0759a6b6d5cc46b05157518a4ce3eb9bf

Reviewed By: blairvanderhoof

Differential Revision: D6575797

fbshipit-source-id: 913a5916def9719689917e83e917f44503b99a60

Reviewed By: adamjernst

Differential Revision: D6569785

fbshipit-source-id: d2f20cd648822846e59830614d4eb0f466252363

Reviewed By: sahrens

Differential Revision: D6573855

fbshipit-source-id: 8768dca7d36782e82fb457f6ff4b09791e669d00

Reviewed By: gabelevi

Differential Revision: D6571796

fbshipit-source-id: 6a6d98b05953f40b825a260f44765689e91269a8

Summary:
Fixes the Flow failure due to an undefined Ast type.

Before:

```
 $ npm run flow -- check

> react-native@1000.0.0 flow /Users/hramos/git/react-native
> flow "check"

Error: local-cli/__tests__/fs-mock-test.js:27
 27:   beforeEach(() => {
       ^^^^^^^^^^ beforeEach. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:53
 53:       expect(content).toEqual('beep');
           ^^^^^^ expect. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:88
 88:         expect(content).toEqual('hello, world!');
             ^^^^^^ expect. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:100
100:       expect(content).toEqual('hello, world!');
           ^^^^^^ expect. Could not resolve name

Error: node_modules/metro/src/Bundler/util.js.flow:46
 46: ): Ast {
        ^^^ Ast. Could not resolve name

Error: node_modules/metro/src/ModuleGraph/worker/collect-dependencies.js.flow:283
283: const xp = (module.exports = (ast: Ast) =>
                                        ^^^ Ast. Could not resolve name

Error: node_modules/metro/src/assetTransformer.js.flow:29
 29: ): Promise<{ast: Ast}> {
                      ^^^ Ast. Could not resolve name
```

After

```
$ npm run flow -- check

> react-native@1000.0.0 flow /Users/hramos/git/react-native
> flow "check"

Error: local-cli/__tests__/fs-mock-test.js:27
 27:   beforeEach(() => {
       ^^^^^^^^^^ beforeEach. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:53
 53:       expect(content).toEqual('beep');
           ^^^^^^ expect. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:88
 88:         expect(content).toEqual('hello, world!');
             ^^^^^^ expect. Could not resolve name

Error: local-cli/__tests__/fs-mock-test.js:100
100:       expect(content).toEqual('hello, world!');
           ^^^^^^ expect. Could not resolve name
```

[ GENERAL ] [ BUGFIX] [ .flowconfig ] - Have Flow ignore Metro node_nodules
Closes https://github.com/facebook/react-native/pull/17187

Differential Revision: D6572303

Pulled By: hramos

fbshipit-source-id: aa256b9725970fcc2a6da6578c83e7c0875e3cfd

Reviewed By: danzimm

Differential Revision: D6568053

fbshipit-source-id: 94fdecaf066a36c9c916bbd7b23c2f0680d91895

Reviewed By: fromcelticpark

Differential Revision: D6445626

fbshipit-source-id: aa37c87f019eea85d76365b6be919adfafc3c27a

Reviewed By: danzimm

Differential Revision: D6570194

fbshipit-source-id: 84dae925b9269393b6925e0977598e3872acb14e

Summary: JSON.stringify will convert a function to null, but folly::dynamic in the native code can't represent a JS function. Props do sometimes have functions, but don't permit them everywhere.

Reviewed By: johnislarry

Differential Revision: D6541878

fbshipit-source-id: b2a9d3ba7899dfb98a6a2ada3aa91a26549fdd94

Reviewed By: shergin

Differential Revision: D6382976

fbshipit-source-id: 33568a241395b085a840ac52adab3c9dc463ea4c