cc: Allow DeferredInitialize to use DelegatingRenderer

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index b3911f86ac186be311f4a8878bd179a1853fdd51..778af346a1d4af3214ee8071a6ae78d322c905a5 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -572,7 +572,10 @@ static DrawMode GetDrawMode(OutputSurface* output_surface) {
     return DRAW_MODE_HARDWARE;
   } else {
     DCHECK_EQ(!output_surface->software_device(),
-              output_surface->capabilities().delegated_rendering);
+              output_surface->capabilities().delegated_rendering &&
+                  !output_surface->capabilities().deferred_gl_initialization)
+        << output_surface->capabilities().delegated_rendering << " "
+        << output_surface->capabilities().deferred_gl_initialization;
     return DRAW_MODE_SOFTWARE;
   }
 }
@@ -1813,12 +1816,13 @@ void LayerTreeHostImpl::ReleaseTreeResources() {
 void LayerTreeHostImpl::CreateAndSetRenderer(
     OutputSurface* output_surface,
     ResourceProvider* resource_provider,
-    bool skip_gl_renderer) {
+    bool force_software_renderer) {
   DCHECK(!renderer_);
-  if (output_surface->capabilities().delegated_rendering) {
+  if (output_surface->capabilities().delegated_rendering &&
+      !force_software_renderer) {

[danakj, 2014/05/20 18:09:51]

Ok I am confused by this change here. Delegated rendering has nothing to do with
hardware vs software, we ship software frames using delegated rendering too. The
only time we couldn't right now is when we want to use SkPicture backed draw
quads (ie resourceless software mode?)

[boliu, 2014/05/20 18:31:49]

Hmm, I think you are right.

The resourceless software mode draw creates its own SoftwareRenderer instance on
the stack for that particular draw, and doesn't need whatever renderer is in
LTHI.

So the SoftwareRenderer created here for webview really is just a place holder
and never used for any draws. And DelegatingRenderer can be created without a
context provider. Then in DeferredInitialize, we tear it down and recreate one
with a context, and everything should just work...

I'll test this now. Assuming it works, this CL will be just DCHECK fixes and
tests, which is just fine with me :)

     renderer_ = DelegatingRenderer::Create(
         this, &settings_, output_surface, resource_provider);
-  } else if (output_surface->context_provider() && !skip_gl_renderer) {
+  } else if (output_surface->context_provider() && !force_software_renderer) {
     renderer_ = GLRenderer::Create(this,
                                    &settings_,
                                    output_surface,
@@ -1945,9 +1949,10 @@ bool LayerTreeHostImpl::InitializeRenderer(
   if (output_surface->capabilities().deferred_gl_initialization)
     EnforceZeroBudget(true);
 
-  bool skip_gl_renderer = false;
+  bool force_software_renderer =
+      output_surface->capabilities().deferred_gl_initialization;
   CreateAndSetRenderer(
-      output_surface.get(), resource_provider.get(), skip_gl_renderer);
+      output_surface.get(), resource_provider.get(), force_software_renderer);
 
   transfer_buffer_memory_limit_ =
       GetMaxTransferBufferUsageBytes(output_surface->context_provider().get());
@@ -2015,9 +2020,9 @@ void LayerTreeHostImpl::DeferredInitialize() {
 
   resource_provider_->InitializeGL();
 
-  bool skip_gl_renderer = false;
+  bool force_software_renderer = false;
   CreateAndSetRenderer(
-      output_surface_.get(), resource_provider_.get(), skip_gl_renderer);
+      output_surface_.get(), resource_provider_.get(), force_software_renderer);
 
   EnforceZeroBudget(false);
   client_->SetNeedsCommitOnImplThread();
@@ -2037,9 +2042,9 @@ void LayerTreeHostImpl::ReleaseGL() {
   staging_resource_pool_.reset();
   resource_provider_->InitializeSoftware();
 
-  bool skip_gl_renderer = true;
+  bool force_software_renderer = true;
   CreateAndSetRenderer(
-      output_surface_.get(), resource_provider_.get(), skip_gl_renderer);
+      output_surface_.get(), resource_provider_.get(), force_software_renderer);
 
   EnforceZeroBudget(true);
   DCHECK(GetRendererCapabilities().using_map_image);