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 70522f2fc0289f7295edba5ffb246e26db4cbe87..e96cc4174088a719e6a9e3f4b372c56207a72629 100644
--- a/cc/direct_renderer.cc
+++ b/cc/direct_renderer.cc
@@ -185,9 +185,12 @@ 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::RectF damageRectInRenderPassSpace = MathUtil::projectClippedRect(inverseTransform, frame.rootDamageRect);
-    renderPassScissor.Intersect(damageRectInRenderPassSpace);
+    gfx::Transform inverseTransform(gfx::Transform::kSkipInitialization);
+    if (frame.currentRenderPass->transform_to_root_target.GetInverse(&inverseTransform)) {
+        // Only intersect inverse-projected damage if the transform is invertible.
+        gfx::RectF damageRectInRenderPassSpace = MathUtil::projectClippedRect(inverseTransform, frame.rootDamageRect);
+        renderPassScissor.Intersect(damageRectInRenderPassSpace);
+    }
 
     return renderPassScissor;
 }