[PPAPI] Add browser tests for compositor API

ppapi/proxy/compositor_resource.cc

Index: ppapi/proxy/compositor_resource.cc
diff --git a/ppapi/proxy/compositor_resource.cc b/ppapi/proxy/compositor_resource.cc
index 3ada734849839aca56078ac7e3859b6d574df1a6..9688f6054bc5d9796fbbfd86eacd16e61445b337 100644
--- a/ppapi/proxy/compositor_resource.cc
+++ b/ppapi/proxy/compositor_resource.cc
@@ -6,6 +6,7 @@
 
 #include "base/logging.h"
 #include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/thunk/enter.h"
 
 namespace ppapi {
 namespace proxy {
@@ -14,6 +15,7 @@ CompositorResource::CompositorResource(Connection connection,
                                        PP_Instance instance)
     : PluginResource(connection, instance),
       layer_reset_(true),
+      bound_to_instance_(false),
       last_resource_id_(0) {
   SendCreate(RENDERER, PpapiHostMsg_Compositor_Create());
 }
@@ -39,6 +41,9 @@ void CompositorResource::OnReplyReceived(
 }
 
 PP_Resource CompositorResource::AddLayer() {
+  if (!bound_to_instance_)
+    return 0;

[piman, 2014/06/18 00:55:24]

Why? It doesn't seem legit.

[Peng, 2014/06/18 02:35:03]

Same reason.

[Peng, 2014/06/18 02:35:03]

I explained the reason in another comment. Please check it.

+
   scoped_refptr<CompositorLayerResource> resource(new CompositorLayerResource(
       connection(), pp_instance(), this));
   layers_.push_back(resource);
@@ -47,6 +52,9 @@ PP_Resource CompositorResource::AddLayer() {
 
 int32_t CompositorResource::CommitLayers(
     const scoped_refptr<ppapi::TrackedCallback>& callback) {
+  if (!bound_to_instance_)
+    return PP_ERROR_FAILED;
+
   if (IsInProgress())
     return PP_ERROR_INPROGRESS;
 
@@ -72,12 +80,41 @@ int32_t CompositorResource::CommitLayers(
 }
 
 int32_t CompositorResource::ResetLayers() {
+  if (!bound_to_instance_)
+    return PP_ERROR_FAILED;
+
   if (IsInProgress())
     return PP_ERROR_INPROGRESS;
+
   ResetLayersInternal();
   return PP_OK;
 }
 
+void CompositorResource::BindToInstance(bool bound) {
+  ProxyLock::AssertAcquiredDebugOnly();
+
+  if (bound == bound_to_instance_)
+    return;
+  bound_to_instance_ = bound;
+
+  // Reset layers when the compositor is un bound from the instance.

[piman, 2014/06/18 00:55:24]

why?

[Peng, 2014/06/18 02:35:03]

Same reason.

+  if (!bound_to_instance_)
+    ResetLayersInternal();
+}
+
+void CompositorResource::NotifyLastPluginRefWasDeleted() {
+  ProxyLock::AssertAcquiredDebugOnly();
+
+  PluginResource::NotifyLastPluginRefWasDeleted();
+  if (bound_to_instance_) {
+    ppapi::thunk::EnterInstanceNoLock enter(pp_instance());
+    CHECK(enter.succeeded());

[piman, 2014/06/18 00:55:24]

no CHECK.

[Peng, 2014/06/18 02:35:03]

Done.

+    enter.functions()->BindGraphics(pp_instance(), 0);

[piman, 2014/06/18 00:55:24]

Why the need to do this? The browser side can do it.

[Peng, 2014/06/18 02:35:03]

Because the plugin will not notify the host, when the last ref is deleted. The
notification is sent in PluginResource's dtor.  So we have to call
BindGraphics(0), so the instance will release a scoped_refptr of the compositor,
and then the compositor will be deleted from the memory.

+    // BindToInstance(0) should be called by PPB_Instance_Proxy::BindGraphics().
+    CHECK(!bound_to_instance_);

[piman, 2014/06/18 00:55:24]

no CHECK.

[Peng, 2014/06/18 02:35:03]

Done.

+   }
+}
+
 void CompositorResource::OnPluginMsgCommitLayersReply(
     const ResourceMessageReplyParams& params) {
   if (!TrackedCallback::IsPending(commit_callback_))