VR Shell: Allow UI elements to determine hit testing.

chrome/browser/android/vr_shell/ui_elements/ui_element.h

Index: chrome/browser/android/vr_shell/ui_elements/ui_element.h
diff --git a/chrome/browser/android/vr_shell/ui_elements/ui_element.h b/chrome/browser/android/vr_shell/ui_elements/ui_element.h
index b0f980772e4a5f8cd4393f9818c09e9921239a77..d915261c11b6f78e0ea98205d72cbc90ae9d33a9 100644
--- a/chrome/browser/android/vr_shell/ui_elements/ui_element.h
+++ b/chrome/browser/android/vr_shell/ui_elements/ui_element.h
@@ -115,6 +115,13 @@ class UiElement : public WorldRectangle {
   virtual void OnMove(gfx::PointF position);
   virtual void OnButtonDown(gfx::PointF position);
   virtual void OnButtonUp(gfx::PointF position);
+  // Whether the point (relative to the origin of the element), should be

[cjgrant, 2017/05/15 16:55:09]

- Typo at "by considered".
- What does "local" mean?
- Maybe say that the incoming 0:1 numbers are relative to the quad, and it's up
to the element to consider those according to its specific shape (round button
is a great example).

[mthiesse, 2017/05/15 21:11:27]

What typo?

Clarified the comment and got rid of the term "local".

[cjgrant, 2017/05/15 21:51:52]

"All elements are by considered rectangular by default"

[mthiesse, 2017/05/15 22:23:32]

I do not see the the problem.

fixed ;)

+  // considered on the element. All elements are by considered rectangular by
+  // default. Local points are mapped as follows, though will extend outside the
+  // rectangular bounds of the element:
+  // [(0.0, 0.0), (1.0, 0.0)
+  //  (1.0, 0.0), (1.0, 1.0)]
+  virtual bool HitTest(gfx::PointF point) const;
 
   int id() const { return id_; }
   void set_id(int id) { id_ = id; }