Bug 756601 - Round texture coords to the nearest texel. r=Bas

gfx/layers/opengl/CompositorOGL.cpp

@@ -546,10 +546,10 @@ CompositorOGL::BindAndDrawQuadWithTextureRect(ShaderProgramOGL *aProg,
   // We need to convert back to actual texels here to get proper behaviour with
   // our GL helper functions. Should fix this sometime.
   // I want to vomit.
-  IntRect texCoordRect = IntRect(aTexCoordRect.x * aTexture->GetSize().width,
+  IntRect texCoordRect = IntRect(roundf(aTexCoordRect.x * aTexture->GetSize().width),
-                                 aTexCoordRect.y * aTexture->GetSize().height,
+                                 roundf(aTexCoordRect.y * aTexture->GetSize().height),
-                                 aTexCoordRect.width * aTexture->GetSize().width,
+                                 roundf(aTexCoordRect.width * aTexture->GetSize().width),
-                                 aTexCoordRect.height * aTexture->GetSize().height);
+                                 roundf(aTexCoordRect.height * aTexture->GetSize().height));
 
   // This is fairly disgusting - if the texture should be flipped it will have a
   // negative height, in which case we un-invert the texture coords and pass the