Simplify mailbox handling in MailboxOutputSurface

content/renderer/gpu/mailbox_output_surface.cc

Index: content/renderer/gpu/mailbox_output_surface.cc
diff --git a/content/renderer/gpu/mailbox_output_surface.cc b/content/renderer/gpu/mailbox_output_surface.cc
index c1166fc80e8343914beffec432a9e6a1651ee884..3af09e29337a4526d95466691a70b869781a4a55 100644
--- a/content/renderer/gpu/mailbox_output_surface.cc
+++ b/content/renderer/gpu/mailbox_output_surface.cc
@@ -47,12 +47,10 @@ void MailboxOutputSurface::EnsureBackbuffer() {
       TransferableFrame& texture = returned_textures_.front();
       if (texture.size == size_) {
         current_backing_ = texture;
-        ConsumeTexture(texture);
         returned_textures_.pop();
         break;
       }
 
-      ConsumeTexture(texture);
       context3d_->deleteTexture(texture.texture_id);
       returned_textures_.pop();
     }
@@ -60,7 +58,6 @@ void MailboxOutputSurface::EnsureBackbuffer() {
     if (!current_backing_.texture_id) {
       current_backing_.texture_id = context3d_->createTexture();
       current_backing_.size = size_;
-      context3d_->genMailboxCHROMIUM(current_backing_.mailbox.name);
       context3d_->bindTexture(GL_TEXTURE_2D, current_backing_.texture_id);
       context3d_->texParameteri(
           GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
@@ -73,6 +70,9 @@ void MailboxOutputSurface::EnsureBackbuffer() {
       context3d_->texImage2D(
           GL_TEXTURE_2D, 0, GL_RGBA, size_.width(), size_.height(), 0,
           GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+      context3d_->genMailboxCHROMIUM(current_backing_.mailbox.name);
+      context3d_->produceTextureCHROMIUM(
+          GL_TEXTURE_2D, current_backing_.mailbox.name);
     }
   }
 }
@@ -87,7 +87,6 @@ void MailboxOutputSurface::DiscardBackbuffer() {
 
   while (!returned_textures_.empty()) {
     const TransferableFrame& frame = returned_textures_.front();
-    ConsumeTexture(frame);
     context3d_->deleteTexture(frame.texture_id);
     returned_textures_.pop();
   }
@@ -128,12 +127,6 @@ void MailboxOutputSurface::SendFrameToParentCompositor(
   DCHECK(size_ == current_backing_.size);
   DCHECK(!current_backing_.mailbox.IsZero());
 
-  context3d_->framebufferTexture2D(
-      GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);

[no sievers, 2013/06/03 22:03:51]

This was necessary for some Android driver that had problems with incomplete
FBOs being bound (even if you did not access the framebuffer). Looks like the
currently bound FBO would just stay complete now though, right?

-  context3d_->bindFramebuffer(GL_FRAMEBUFFER, 0);
-  context3d_->bindTexture(GL_TEXTURE_2D, current_backing_.texture_id);
-  context3d_->produceTextureCHROMIUM(
-      GL_TEXTURE_2D, current_backing_.mailbox.name);
   frame->gl_frame_data->mailbox = current_backing_.mailbox;
   frame->gl_frame_data->size = current_backing_.size;
   context3d_->flush();
@@ -165,7 +158,6 @@ void MailboxOutputSurface::OnSwapAck(const cc::CompositorFrameAck& ack) {
     if (!is_backbuffer_discarded_) {
       returned_textures_.push(*it);
     } else {
-      ConsumeTexture(*it);
       context3d_->deleteTexture(it->texture_id);
     }
 
@@ -195,15 +187,6 @@ void MailboxOutputSurface::PostSubBuffer(gfx::Rect rect,
   DCHECK(GetNumAcksPending() < 2);
 }
 
-void MailboxOutputSurface::ConsumeTexture(const TransferableFrame& frame) {
-  DCHECK(!frame.mailbox.IsZero());
-  if (frame.sync_point)
-    context3d_->waitSyncPoint(frame.sync_point);
-
-  context3d_->bindTexture(GL_TEXTURE_2D, frame.texture_id);
-  context3d_->consumeTextureCHROMIUM(GL_TEXTURE_2D, frame.mailbox.name);
-}
-
 size_t MailboxOutputSurface::GetNumAcksPending() {
   DCHECK(pending_textures_.size());
   return pending_textures_.size() - 1;