Bug 1311642 - Remove BeginUpdate and EndUpdate from GLTextureImage. r=nical

Only DirectUpdate was actually being used, so remove the dead
code. TextureImageCGL does't do anything over BasicTextureImage any more
so remove it too.

MozReview-Commit-ID: D7jpC9M7aTT

gfx/layers/opengl/TextureHostOGL.cpp

@@ -193,9 +193,6 @@ TextureImageTextureSourceOGL::Update(gfx::DataSourceSurface* aSurface,
 
   mTexImage->UpdateFromDataSource(aSurface, aDestRegion, aSrcOffset);
 
-  if (mTexImage->InUpdate()) {
-    mTexImage->EndUpdate();
-  }
   return true;
 }