Create stubs for the FramebufferImpl class.

BUG=angle:841

Change-Id: I089409981604abe9c65c3019765d8d9eeffe38f5
Reviewed-on: https://chromium-review.googlesource.com/232381
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index 404323a..c02bbe6 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -186,7 +186,8 @@
         mHasBeenCurrent = true;
     }
 
-    Framebuffer *framebufferZero = new DefaultFramebuffer(mRenderer->createDefaultAttachment(GL_BACK, surface),
+    Framebuffer *framebufferZero = new DefaultFramebuffer(mRenderer->createFramebuffer(),
+                                                          mRenderer->createDefaultAttachment(GL_BACK, surface),
                                                           mRenderer->createDefaultAttachment(GL_DEPTH, surface),
                                                           mRenderer->createDefaultAttachment(GL_STENCIL, surface));
 
@@ -522,7 +523,7 @@
 {
     if (!getFramebuffer(framebuffer))
     {
-        mFramebufferMap[framebuffer] = new Framebuffer(framebuffer);
+        mFramebufferMap[framebuffer] = new Framebuffer(mRenderer->createFramebuffer(), framebuffer);
     }
 
     mState.setReadFramebufferBinding(getFramebuffer(framebuffer));
@@ -532,7 +533,7 @@
 {
     if (!getFramebuffer(framebuffer))
     {
-        mFramebufferMap[framebuffer] = new Framebuffer(framebuffer);
+        mFramebufferMap[framebuffer] = new Framebuffer(mRenderer->createFramebuffer(), framebuffer);
     }
 
     mState.setDrawFramebufferBinding(getFramebuffer(framebuffer));