Remove weak pointers from CastSocket.

extensions/browser/api/cast_channel/cast_channel_apitest.cc

Index: extensions/browser/api/cast_channel/cast_channel_apitest.cc
diff --git a/extensions/browser/api/cast_channel/cast_channel_apitest.cc b/extensions/browser/api/cast_channel/cast_channel_apitest.cc
index 14f1fbd29a9e806957adcc8fc4cb1047b934987c..9f56d2d6e7158d1d1e51dadae6a61b9e56ae10fc 100644
--- a/extensions/browser/api/cast_channel/cast_channel_apitest.cc
+++ b/extensions/browser/api/cast_channel/cast_channel_apitest.cc
@@ -20,6 +20,9 @@
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gmock_mutant.h"
 
+// TODO(mfoltz): Mock out the ApiResourceManager to resolve threading issues
+// (crbug.com/398242) and simulate unloading of the extension.
+
 namespace cast_channel = extensions::core_api::cast_channel;
 using cast_channel::CastSocket;
 using cast_channel::ChannelError;
@@ -69,11 +72,6 @@ class MockCastSocket : public CastSocket {
                  base::TimeDelta::FromMilliseconds(kTimeoutMs)) {}
   virtual ~MockCastSocket() {}
 
-  virtual bool CalledOnValidThread() const OVERRIDE {
-    // Always return true in testing.
-    return true;
-  }
-
   MOCK_METHOD1(Connect, void(const net::CompletionCallback& callback));
   MOCK_METHOD2(SendMessage, void(const MessageInfo& message,
                                  const net::CompletionCallback& callback));