Revert "Make FramebufferAttachmentObject not refcountable"

BUG=

This reverts commit 19ba57469aa02074d094a9aef104f84d0b6d881e.

Change-Id: I5dce6c8a81570e22affbcaf32183a97c97849718
Reviewed-on: https://chromium-review.googlesource.com/293351
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Tested-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index 05b9d55..fda3e8f 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -36,15 +36,9 @@
 namespace gl
 {
 
-Context::Context(const egl::Config *config,
-                 int clientVersion,
-                 const Context *shareContext,
-                 rx::Renderer *renderer,
-                 bool notifyResets,
-                 bool robustAccess)
+Context::Context(const egl::Config *config, int clientVersion, const Context *shareContext, rx::Renderer *renderer, bool notifyResets, bool robustAccess)
     : mRenderer(renderer),
       mConfig(config),
-      mCurrentSurface(nullptr),
       mData(clientVersion, mState, mCaps, mTextureCaps, mExtensions, nullptr)
 {
     ASSERT(robustAccess == false);   // Unimplemented
@@ -169,11 +163,6 @@
     }
     mZeroTextures.clear();
 
-    if (mCurrentSurface != nullptr)
-    {
-        releaseSurface();
-    }
-
     if (mResourceManager)
     {
         mResourceManager->release();
@@ -200,15 +189,6 @@
     // TODO(jmadill): Rework this when we support ContextImpl
     mState.setAllDirtyBits();
 
-    if (mCurrentSurface)
-    {
-        releaseSurface();
-    }
-
-    ASSERT(mCurrentSurface == nullptr);
-    mCurrentSurface = surface;
-    surface->setIsCurrent(true);
-
     // Update default framebuffer
     Framebuffer *defaultFBO = mFramebufferMap[0];
 
@@ -250,16 +230,9 @@
 void Context::releaseSurface()
 {
     Framebuffer *defaultFBO = mFramebufferMap[0];
-    if (defaultFBO)
-    {
-        defaultFBO->resetAttachment(GL_BACK);
-        defaultFBO->resetAttachment(GL_DEPTH);
-        defaultFBO->resetAttachment(GL_STENCIL);
-    }
-
-    ASSERT(mCurrentSurface != nullptr);
-    mCurrentSurface->setIsCurrent(false);
-    mCurrentSurface = nullptr;
+    defaultFBO->resetAttachment(GL_BACK);
+    defaultFBO->resetAttachment(GL_DEPTH);
+    defaultFBO->resetAttachment(GL_STENCIL);
 }
 
 // NOTE: this function should not assume that this context is current!