Use SocketRocket for web socket library (facebook#36347)

Summary:
The previous native web socket API, `RCTSRWebSocket`, appears to be an older version of the one provided as part of [SocketRocket](https://github.com/facebookincubator/SocketRocket). The latter has several improvements, such as the ability to respect proxy settings, which has been requested by a user of a React Native app.

Everything translates over pretty easily, and considering that SocketRocket is already a dependency of Flipper, there doesn't seem to be much additional cost to swapping out the libraries. If we wanted to make things even slimmer, it may even be possible to make the WebSocket library be optional for release builds.

## Changelog

[IOS] [CHANGED] - Use SocketRocket for web socket library

Pull Request resolved: facebook#36347

Test Plan:
Validated the following:
* The WebSocket test page in RNTester
* Live reloading

Differential Revision: D43768835

Pulled By: javache

fbshipit-source-id: 4be7de1fce2183133462c0243b4b3309b02043f5

Author: Adam Gleitman

BUCK

@@ -320,7 +320,6 @@ REACT_PUBLIC_HEADERS = {
     "React/RCTRootShadowView.h": RCTVIEWS_PATH + "RCTRootShadowView.h",
     "React/RCTRootView.h": RCTBASE_PATH + "RCTRootView.h",
     "React/RCTRootViewDelegate.h": RCTBASE_PATH + "RCTRootViewDelegate.h",
-    "React/RCTSRWebSocket.h": RCTLIB_PATH + "WebSocket/RCTSRWebSocket.h",
     "React/RCTScrollEvent.h": RCTVIEWS_PATH + "ScrollView/RCTScrollEvent.h",
     "React/RCTScrollView.h": RCTVIEWS_PATH + "ScrollView/RCTScrollView.h",
     "React/RCTScrollableProtocol.h": RCTVIEWS_PATH + "ScrollView/RCTScrollableProtocol.h",
@@ -454,6 +453,7 @@ rn_apple_xplat_cxx_library(
     ],
     deps = [
         YOGA_CXX_TARGET,
+        "//fbobjc/VendorLib/SocketRocket:SocketRocket",
         react_native_xplat_target("cxxreact:bridge"),
         react_native_xplat_target("reactperflogger:reactperflogger"),
     ],

Libraries/WebSocket/RCTReconnectingWebSocket.m

@@ -10,16 +10,16 @@
 #import <React/RCTConvert.h>
 #import <React/RCTDefines.h>
 
-#import <React/RCTSRWebSocket.h>
+#import <SocketRocket/SRWebSocket.h>
 
 #if RCT_DEV // Only supported in dev mode
 
-@interface RCTReconnectingWebSocket () <RCTSRWebSocketDelegate>
+@interface RCTReconnectingWebSocket () <SRWebSocketDelegate>
 @end
 
 @implementation RCTReconnectingWebSocket {
   NSURL *_url;
-  RCTSRWebSocket *_socket;
+  SRWebSocket *_socket;
   BOOL _stopped;
 }
 
@@ -39,14 +39,14 @@ - (instancetype)initWithURL:(NSURL *)url
 
 - (void)send:(id)data
 {
-  [_socket send:data];
+  [_socket sendData:data error:nil];
 }
 
 - (void)start
 {
   [self stop];
   _stopped = NO;
-  _socket = [[RCTSRWebSocket alloc] initWithURL:_url];
+  _socket = [[SRWebSocket alloc] initWithURL:_url];
   _socket.delegate = self;
   [_socket setDelegateDispatchQueue:_delegateDispatchQueue];
   [_socket open];
@@ -60,7 +60,7 @@ - (void)stop
   _socket = nil;
 }
 
-- (void)webSocket:(RCTSRWebSocket *)webSocket didReceiveMessage:(id)message
+- (void)webSocket:(SRWebSocket *)webSocket didReceiveMessage:(id)message
 {
   [_delegate reconnectingWebSocket:self didReceiveMessage:message];
 }
@@ -71,7 +71,7 @@ - (void)reconnect
     return;
   }
 
-  __weak RCTSRWebSocket *socket = _socket;
+  __weak SRWebSocket *socket = _socket;
   __weak __typeof(self) weakSelf = self;
 
   dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(2 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
@@ -82,20 +82,20 @@ - (void)reconnect
   });
 }
 
-- (void)webSocketDidOpen:(RCTSRWebSocket *)webSocket
+- (void)webSocketDidOpen:(SRWebSocket *)webSocket
 {
   [_delegate reconnectingWebSocketDidOpen:self];
 }
 
-- (void)webSocket:(RCTSRWebSocket *)webSocket didFailWithError:(NSError *)error
+- (void)webSocket:(SRWebSocket *)webSocket didFailWithError:(NSError *)error
 {
   [_delegate reconnectingWebSocketDidClose:self];
   if ([error code] != ECONNREFUSED) {
     [self reconnect];
   }
 }
 
-- (void)webSocket:(RCTSRWebSocket *)webSocket
+- (void)webSocket:(SRWebSocket *)webSocket
     didCloseWithCode:(NSInteger)code
               reason:(NSString *)reason
             wasClean:(BOOL)wasClean