refactoring mouse lock to support pepper and WebKit

webkit/plugins/ppapi/ppapi_plugin_instance.cc

Index: webkit/plugins/ppapi/ppapi_plugin_instance.cc
diff --git a/webkit/plugins/ppapi/ppapi_plugin_instance.cc b/webkit/plugins/ppapi/ppapi_plugin_instance.cc
index 7f849f6537805b61a80ffa96b34dfa7b954e7349..23a18628c751af1bf7de23bbc9dab285debc67c7 100644
--- a/webkit/plugins/ppapi/ppapi_plugin_instance.cc
+++ b/webkit/plugins/ppapi/ppapi_plugin_instance.cc
@@ -1675,13 +1675,13 @@ bool PluginInstance::IsFullPagePlugin() const {
   return frame->view()->mainFrame()->document().isPluginDocument();
 }
 
-void PluginInstance::OnLockMouseACK(int32_t result) {
+void PluginInstance::OnLockMouseACK(bool succeeded) {
   if (!lock_mouse_callback_.func) {
     NOTREACHED();
     return;
   }
-
-  PP_RunAndClearCompletionCallback(&lock_mouse_callback_, result);
+  PP_RunAndClearCompletionCallback(&lock_mouse_callback_,
+                                   succeeded ? PP_OK : PP_ERROR_FAILED);
 }
 
 void PluginInstance::OnMouseLockLost() {
@@ -1689,6 +1689,13 @@ void PluginInstance::OnMouseLockLost() {
     plugin_mouse_lock_interface_->MouseLockLost(pp_instance());
 }
 
+void PluginInstance::HandleMouseLockedInputEvent(
+    const WebKit::WebMouseEvent& event) {
+  // |cursor_info| is ignored since it is hidden when the mouse is locked.
+  WebKit::WebCursorInfo cursor_info;
+  HandleInputEvent(event, &cursor_info);
+}
+
 void PluginInstance::SimulateInputEvent(const InputEventData& input_event) {
   WebView* web_view = container()->element().document().frame()->view();
   if (!web_view) {
@@ -1974,16 +1981,21 @@ int32_t PluginInstance::LockMouse(PP_Instance instance,
     // Don't support synchronous call.
     return PP_ERROR_BLOCKS_MAIN_THREAD;
   }
-  if (lock_mouse_callback_.func)
+  if (lock_mouse_callback_.func)  // A lock is pending.
     return PP_ERROR_INPROGRESS;
+
+  if (delegate()->IsMouseLocked(this))
+    return PP_OK;
+
   if (!CanAccessMainFrame())
     return PP_ERROR_NOACCESS;
 
-  lock_mouse_callback_ = callback;
-  // We will be notified on completion via OnLockMouseACK(), either
-  // synchronously or asynchronously.
-  delegate()->LockMouse(this);
-  return PP_OK_COMPLETIONPENDING;
+  if (delegate()->LockMouse(this)) {
+    lock_mouse_callback_ = callback;
+    return PP_OK_COMPLETIONPENDING;
+  } else {
+    return PP_ERROR_FAILED;

[piman, 2012/01/18 19:00:59]

This function doesn't respect the "always asynchronous unless
PP_COMPLETIONCALLBACK_FLAG_OPTIONAL is specified" semantics on the completion
callback. Can we fix that?
We'd really want the same exact semantics as TrackedCallback, but associated
with the instance (instead of a resource).

[yzshen1, 2012/01/18 19:21:42]

I think that semantics is guaranteed by the thunk layer. In
ppb_mouse_lock_thunk.cc, we have MayForceCallback():
http://code.google.com/codesearch#OAMlx_jo-ck/src/ppapi/thunk/ppb_mouse_lock_...

[piman, 2012/01/18 19:26:00]

Ah, ok, that works too. Thanks!

+  }
 }
 
 void PluginInstance::UnlockMouse(PP_Instance instance) {