Revert "Refactor code listening to platform events in content/renderer/."

content/renderer/gamepad_shared_memory_reader.cc

Index: content/renderer/gamepad_shared_memory_reader.cc
diff --git a/content/renderer/gamepad_shared_memory_reader.cc b/content/renderer/gamepad_shared_memory_reader.cc
index 5f8d31aa5705d988c76c1535da6acfaf26bad1d3..e74f02581864cff2d5c4dc4b4f44081826a3ccdb 100644
--- a/content/renderer/gamepad_shared_memory_reader.cc
+++ b/content/renderer/gamepad_shared_memory_reader.cc
@@ -12,28 +12,24 @@
 #include "content/renderer/renderer_webkitplatformsupport_impl.h"
 #include "ipc/ipc_sync_message_filter.h"
 #include "third_party/WebKit/public/platform/WebGamepadListener.h"
-#include "third_party/WebKit/public/platform/WebPlatformEventListener.h"
 
 namespace content {
 
-GamepadSharedMemoryReader::GamepadSharedMemoryReader(RenderThread* thread)
-    : RendererGamepadProvider(thread),
-      gamepad_hardware_buffer_(NULL),
+GamepadSharedMemoryReader::GamepadSharedMemoryReader(
+    RendererWebKitPlatformSupportImpl* webkit_platform_support)
+    : gamepad_hardware_buffer_(NULL),
+      gamepad_listener_(NULL),
+      is_polling_(false),
       ever_interacted_with_(false) {
+  webkit_platform_support->set_gamepad_provider(this);
 }
 
-void GamepadSharedMemoryReader::SendStartMessage() {
+void GamepadSharedMemoryReader::StartPollingIfNecessary() {
+  if (is_polling_)
+    return;
+
   CHECK(RenderThread::Get()->Send(new GamepadHostMsg_StartPolling(
       &renderer_shared_memory_handle_)));
-}
-
-void GamepadSharedMemoryReader::SendStopMessage() {
-    RenderThread::Get()->Send(new GamepadHostMsg_StopPolling());
-}
-
-void GamepadSharedMemoryReader::Start(
-    blink::WebPlatformEventListener* listener) {
-  PlatformEventObserver::Start(listener);
 
   // If we don't get a valid handle from the browser, don't try to Map (we're
   // probably out of memory or file handles).
@@ -50,11 +46,24 @@ void GamepadSharedMemoryReader::Start(
   CHECK(memory);
   gamepad_hardware_buffer_ =
       static_cast<GamepadHardwareBuffer*>(memory);
+
+  is_polling_ = true;
+}
+
+void GamepadSharedMemoryReader::StopPollingIfNecessary() {
+  if (is_polling_) {
+    RenderThread::Get()->Send(new GamepadHostMsg_StopPolling());
+    is_polling_ = false;
+  }
 }
 
 void GamepadSharedMemoryReader::SampleGamepads(blink::WebGamepads& gamepads) {
-  // Blink should have started observing at that point.
-  CHECK(is_observing());
+  // Blink should set the listener before start sampling.
+  CHECK(gamepad_listener_);
+
+  StartPollingIfNecessary();
+  if (!is_polling_)
+    return;
 
   // ==========
   //   DANGER
@@ -104,7 +113,20 @@ void GamepadSharedMemoryReader::SampleGamepads(blink::WebGamepads& gamepads) {
   }
 }
 
+void GamepadSharedMemoryReader::SetGamepadListener(
+    blink::WebGamepadListener* listener) {
+  gamepad_listener_ = listener;
+  if (gamepad_listener_) {
+    // Polling has to be started rigth now and not just on the first sampling
+    // because want to get connection events from now.
+    StartPollingIfNecessary();
+  } else {
+    StopPollingIfNecessary();
+  }
+}
+
 GamepadSharedMemoryReader::~GamepadSharedMemoryReader() {
+  StopPollingIfNecessary();
 }
 
 bool GamepadSharedMemoryReader::OnControlMessageReceived(
@@ -124,15 +146,15 @@ void GamepadSharedMemoryReader::OnGamepadConnected(
   // The browser already checks if the user actually interacted with a device.
   ever_interacted_with_ = true;
 
-  if (listener())
-    listener()->didConnectGamepad(index, gamepad);
+  if (gamepad_listener_)
+    gamepad_listener_->didConnectGamepad(index, gamepad);
 }
 
 void GamepadSharedMemoryReader::OnGamepadDisconnected(
     int index,
     const blink::WebGamepad& gamepad) {
-  if (listener())
-    listener()->didDisconnectGamepad(index, gamepad);
+  if (gamepad_listener_)
+    gamepad_listener_->didDisconnectGamepad(index, gamepad);
 }
 
 } // namespace content