Revert of command_buffer_gles2: Implement EGL default Display as a global object

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index 70b99be9743a1a7f8e00b38f17aca36e05671776..901d6abfecf90881e1fc72b5725f4e1e208d513c 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -594,7 +594,6 @@
                   const std::vector<int32_t>& attribs) override;
   void Destroy(bool have_context) override;
   void SetSurface(const scoped_refptr<gfx::GLSurface>& surface) override;
-  void ReleaseSurface() override;
   void ProduceFrontBuffer(const Mailbox& mailbox) override;
   bool ResizeOffscreenFrameBuffer(const gfx::Size& size) override;
   void UpdateParentTextureInfo();
@@ -3712,7 +3711,6 @@
 // }  // anonymous namespace
 
 bool GLES2DecoderImpl::MakeCurrent() {
-  DCHECK(surface_);
   if (!context_.get())
     return false;
 
@@ -4270,20 +4268,9 @@
 void GLES2DecoderImpl::SetSurface(
     const scoped_refptr<gfx::GLSurface>& surface) {
   DCHECK(context_->IsCurrent(NULL));
-  DCHECK(surface);
+  DCHECK(surface_.get());
   surface_ = surface;
   RestoreCurrentFramebufferBindings();
-}
-
-void GLES2DecoderImpl::ReleaseSurface() {
-  if (!context_.get())
-    return;
-  if (WasContextLost()) {
-    DLOG(ERROR) << "  GLES2DecoderImpl: Trying to release lost context.";
-    return;
-  }
-  context_->ReleaseCurrent(surface_.get());
-  surface_ = nullptr;
 }
 
 void GLES2DecoderImpl::ProduceFrontBuffer(const Mailbox& mailbox) {