Implement the gamepad API in the IPC proxy

content/browser/renderer_host/gamepad_browser_message_filter.cc

Index: content/browser/renderer_host/gamepad_browser_message_filter.cc
diff --git a/content/browser/renderer_host/gamepad_browser_message_filter.cc b/content/browser/renderer_host/gamepad_browser_message_filter.cc
index 3701c7ff758b113c29c630f748a1adadd82fb44b..c06eec28dce8bb5e585f5da13ae4fa6844e6b15a 100644
--- a/content/browser/renderer_host/gamepad_browser_message_filter.cc
+++ b/content/browser/renderer_host/gamepad_browser_message_filter.cc
@@ -11,12 +11,14 @@ using content::BrowserMessageFilter;
 
 namespace content {
 
-GamepadBrowserMessageFilter::GamepadBrowserMessageFilter(
-    content::RenderProcessHost* render_process_host)
-    : render_process_host_(render_process_host) {
+GamepadBrowserMessageFilter::GamepadBrowserMessageFilter()
+    : is_started_(false) {
 }
 
 GamepadBrowserMessageFilter::~GamepadBrowserMessageFilter() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  if (is_started_)
+    GamepadService::GetInstance()->RemoveConsumer();
 }
 
 bool GamepadBrowserMessageFilter::OnMessageReceived(
@@ -36,13 +38,25 @@ bool GamepadBrowserMessageFilter::OnMessageReceived(
 void GamepadBrowserMessageFilter::OnGamepadStartPolling(
     base::SharedMemoryHandle* renderer_handle) {
   GamepadService* service = GamepadService::GetInstance();
-  service->Start(NULL, render_process_host_);
-  *renderer_handle = service->GetSharedMemoryHandle(peer_handle());
+  if (!is_started_) {
+    is_started_ = true;
+    service->AddConsumer();
+    *renderer_handle = service->GetSharedMemoryHandleForProcess(peer_handle());
+  } else {
+    // Currently we only expect the renderer to tell us once to start.
+    NOTREACHED();
+  }
 }
 
 void GamepadBrowserMessageFilter::OnGamepadStopPolling() {
   // TODO(scottmg): Probably get rid of this message. We can't trust it will
   // arrive anyway if the renderer crashes, etc.
+  if (is_started_) {
+    is_started_ = false;
+    GamepadService::GetInstance()->RemoveConsumer();
+  } else {
+    NOTREACHED();
+  }
 }
 
-} // namespace content
+}  // namespace content