command_buffer: Defer restoring of FBO bindings when changing virtual contexts

gpu/command_buffer/service/framebuffer_manager.cc

Index: gpu/command_buffer/service/framebuffer_manager.cc
diff --git a/gpu/command_buffer/service/framebuffer_manager.cc b/gpu/command_buffer/service/framebuffer_manager.cc
index d64963534a345c6d92b47e65de94fff5b691253b..6b8fa8ca2b98c7b7efaabe6ed3658e29f4e3e898 100644
--- a/gpu/command_buffer/service/framebuffer_manager.cc
+++ b/gpu/command_buffer/service/framebuffer_manager.cc
@@ -36,14 +36,70 @@ bool DetectWebGL1DepthStencilAttachmentConflicts(
 }  // namespace anonymous
 
 DecoderFramebufferState::DecoderFramebufferState()
-    : clear_state_dirty(false),
-      bound_read_framebuffer(NULL),
-      bound_draw_framebuffer(NULL) {
-}
+    : draw_binding_dirty_(true),
+      read_binding_dirty_(true),
+      draw_framebuffer_clear_state_dirty_(true) {}
 
 DecoderFramebufferState::~DecoderFramebufferState() {
 }
 
+void DecoderFramebufferState::set_bound_draw_framebuffer(
+    Framebuffer* framebuffer) {
+  if (bound_draw_framebuffer_ == framebuffer)
+    return;
+  bound_draw_framebuffer_ = framebuffer;
+  draw_binding_dirty_ = true;
+  draw_framebuffer_clear_state_dirty_ = true;
+}
+
+void DecoderFramebufferState::set_bound_read_framebuffer(
+    Framebuffer* framebuffer) {
+  if (bound_read_framebuffer_ == framebuffer)
+    return;
+  bound_read_framebuffer_ = framebuffer;
+  read_binding_dirty_ = true;
+}
+
+void DecoderFramebufferState::NotifyFramebufferChanged(
+    Framebuffer* framebuffer) {
+  if (framebuffer == bound_draw_framebuffer_.get())
+    draw_framebuffer_clear_state_dirty_ = true;
+}
+
+void DecoderFramebufferState::NotifyBoundFramebuffersChanged() {
+  draw_framebuffer_clear_state_dirty_ = true;
+}
+
+void DecoderFramebufferState::SetBoundFramebuffer(GLenum target,
+                                                  Framebuffer* framebuffer) {
+  if (target == GL_FRAMEBUFFER || target == GL_DRAW_FRAMEBUFFER_EXT)
+    set_bound_draw_framebuffer(framebuffer);
+  if (target == GL_FRAMEBUFFER || target == GL_READ_FRAMEBUFFER_EXT)
+    set_bound_read_framebuffer(framebuffer);
+}
+
+bool DecoderFramebufferState::IsBindingDirty(GLenum target) const {
+  if (target == GL_READ_FRAMEBUFFER_EXT)
+    return read_binding_dirty_;
+  if (target == GL_DRAW_FRAMEBUFFER_EXT)
+    return draw_binding_dirty_;
+  return read_binding_dirty_ || draw_binding_dirty_;
+}
+
+void DecoderFramebufferState::MarkBindingDirty(GLenum target) {
+  if (target == GL_FRAMEBUFFER || target == GL_DRAW_FRAMEBUFFER_EXT)
+    draw_binding_dirty_ = true;
+  if (target == GL_FRAMEBUFFER || target == GL_READ_FRAMEBUFFER_EXT)
+    read_binding_dirty_ = true;
+}
+
+void DecoderFramebufferState::MarkBindingClean(GLenum target) {
+  if (target == GL_FRAMEBUFFER || target == GL_DRAW_FRAMEBUFFER_EXT)
+    draw_binding_dirty_ = false;
+  if (target == GL_FRAMEBUFFER || target == GL_READ_FRAMEBUFFER_EXT)
+    read_binding_dirty_ = false;
+}
+
 class RenderbufferAttachment
     : public Framebuffer::Attachment {
  public: