Migrate from MathUtil::inverse() to gfx::Transform::GetInverse()

cc/direct_renderer.cc

Index: cc/direct_renderer.cc
diff --git a/cc/direct_renderer.cc b/cc/direct_renderer.cc
index d5dc97593319a43ba6f9fb9989630debb7563054..0e876a8e674f18c5d26a38bab9fb2f557c763147 100644
--- a/cc/direct_renderer.cc
+++ b/cc/direct_renderer.cc
@@ -187,7 +187,8 @@ gfx::RectF DirectRenderer::computeScissorRectForRenderPass(const DrawingFrame& f
     if (frame.rootDamageRect == frame.rootRenderPass->output_rect)
         return renderPassScissor;
 
-    gfx::Transform inverseTransform = MathUtil::inverse(frame.currentRenderPass->transform_to_root_target);
+    gfx::Transform inverseTransform(gfx::Transform::kSkipInitialization);
+    frame.currentRenderPass->transform_to_root_target.GetInverse(&inverseTransform);

[danakj, 2012/12/19 05:23:06]

I don't see a check for invertible here. Should we do something with the return
value from GetInverse()?

Maybe early out and return renderPassScissor unintersected?

     gfx::RectF damageRectInRenderPassSpace = MathUtil::projectClippedRect(inverseTransform, frame.rootDamageRect);
     renderPassScissor.Intersect(damageRectInRenderPassSpace);