Apple TV Cocoapods support

Summary:
**Motivation**

Support Apple TV for people adding React Native to their projects using Cocoapods.

**Test plan**

Working test project at https://github.com/dlowder-salesforce/react-native-tvos-cocoapods-test
Closes https://github.com/facebook/react-native/pull/15065

Differential Revision: D5443791

Pulled By: javache

fbshipit-source-id: dc46a72df0d73a0049f1c3f9368658e5f3d1ecb8

React.podspec

@@ -36,7 +36,7 @@ Pod::Spec.new do |s|
   s.source                  = source
   s.default_subspec         = "Core"
   s.requires_arc            = true
-  s.platform                = :ios, "8.0"
+  s.platforms               = { :ios => "8.0", :tvos => "9.2" }
   s.pod_target_xcconfig     = { "CLANG_CXX_LANGUAGE_STANDARD" => "c++14" }
   s.preserve_paths          = "package.json", "LICENSE", "LICENSE-docs", "PATENTS"
   s.cocoapods_version       = ">= 1.2.0"
@@ -48,11 +48,18 @@ Pod::Spec.new do |s|
                               "IntegrationTests/*",
                               "React/DevSupport/*",
                               "React/Inspector/*",
-                              "React/**/RCTTVView.*",
                               "ReactCommon/yoga/*",
                               "React/Cxx*/*",
                               "React/Base/RCTBatchedBridge.mm",
                               "React/Executors/*"
+    ss.ios.exclude_files    = "React/**/RCTTVView.*"
+    ss.tvos.exclude_files   = "React/Modules/RCTClipboard*",
+                              "React/Views/RCTDatePicker*",
+                              "React/Views/RCTPicker*",
+                              "React/Views/RCTRefreshControl*",
+                              "React/Views/RCTSlider*",
+                              "React/Views/RCTSwitch*",
+                              "React/Views/RCTWebView*"
     ss.header_dir           = "React"
     ss.framework            = "JavaScriptCore"
     ss.libraries            = "stdc++"

ReactCommon/yoga/Yoga.podspec

@@ -34,7 +34,7 @@ Pod::Spec.new do |spec|
   ]
 
   # Pinning to the same version as React.podspec.
-  spec.platform = :ios, "8.0"
+  spec.platforms = { :ios => "8.0", :tvos => "9.2" }
 
   # Set this environment variable when not using the `:path` option to install the pod.
   # E.g. when publishing this spec to a spec repo.

third-party-podspecs/DoubleConversion.podspec

@@ -12,6 +12,6 @@ Pod::Spec.new do |spec|
   spec.source_files = 'double-conversion/*.{h,cc}'
 
   # Pinning to the same version as React.podspec.
-  spec.platform = :ios, '8.0'
+  spec.platforms = { :ios => "8.0", :tvos => "9.2" }
 
 end

third-party-podspecs/Folly.podspec

@@ -31,5 +31,5 @@ Pod::Spec.new do |spec|
                                "HEADER_SEARCH_PATHS" => "\"$(PODS_TARGET_SRCROOT)\" \"$(PODS_ROOT)/boost\" \"$(PODS_ROOT)/DoubleConversion\"" }
 
   # Pinning to the same version as React.podspec.
-  spec.platform = :ios, '8.0'
+  spec.platforms = { :ios => "8.0", :tvos => "9.2" }
 end

third-party-podspecs/GLog.podspec

@@ -27,6 +27,6 @@ Pod::Spec.new do |spec|
                                "HEADER_SEARCH_PATHS" => "$(PODS_TARGET_SRCROOT)/src" }
 
   # Pinning to the same version as React.podspec.
-  spec.platform = :ios, "8.0"
+  spec.platforms = { :ios => "8.0", :tvos => "9.2" }
 
 end