Changes subtreeShouldRenderToSeparateSurface logic to account for explicit clipping

cc/draw_properties.h

Index: cc/draw_properties.h
diff --git a/cc/draw_properties.h b/cc/draw_properties.h
index 3895ef0720ab675044c7f7f9d63142261ac8e3ed..d57c08332ac45ff329e52a80c9d81ab808d137bd 100644
--- a/cc/draw_properties.h
+++ b/cc/draw_properties.h
@@ -55,6 +55,9 @@ struct CC_EXPORT DrawProperties {
     // True if the layer needs to be clipped by clipRect.
     bool is_clipped;
 
+    // True if all chilren can clip to this layer (if is_clipped is true)
+    bool all_children_can_clip;

[shawnsingh, 2012/12/14 07:34:44]

We should definitely add another line to the DrawProperties constructor defined
above, to initialize this correctly.

[whunt, 2012/12/14 18:17:01]

I'm happy to do this but I object to the word "definitely".  This value is
always initialized in the pre-walk before it is used.  If it's not initialized
there it's pretty meaningless.  Also we've already defined it to be meaningless
if is_clipped is false, which is set by default.  Also, it's not clear what the
correct default value should be.  I can set it to false but again, that's not
really any more meaningful than undefined.

On 2012/12/14 07:34:44, shawnsingh wrote:

+
     // The layer whose coordinate space this layer draws into. This can be
     // either the same layer (m_drawProperties.render_target == this) or an
     // ancestor of this layer.