Add detection for rotation and flip overlay transforms

cc/base/math_util.cc

Index: cc/base/math_util.cc
diff --git a/cc/base/math_util.cc b/cc/base/math_util.cc
index e2fd565eb9774943c0c75c64ada9906fc1804ebb..979bd6e28e62e6a1accb997a4512e151254b8c8a 100644
--- a/cc/base/math_util.cc
+++ b/cc/base/math_util.cc
@@ -15,6 +15,7 @@
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/geometry/vector2d_f.h"
+#include "ui/gfx/geometry/vector3d_f.h"
 #include "ui/gfx/transform.h"
 
 namespace cc {
@@ -867,4 +868,16 @@ float MathUtil::AsFloatSafely(float value) {
   return std::min(value, std::numeric_limits<float>::max());
 }
 
+gfx::Vector3dF MathUtil::GetXAxis(const gfx::Transform& transform) {
+  return gfx::Vector3dF(transform.matrix().get(0, 0),

[danakj, 2015/05/12 23:32:15]

getFloat() for all of these

[halliwell, 2015/05/13 00:49:50]

Done.

+                        transform.matrix().get(1, 0),
+                        transform.matrix().get(2, 0));
+}
+
+gfx::Vector3dF MathUtil::GetYAxis(const gfx::Transform& transform) {
+  return gfx::Vector3dF(transform.matrix().get(0, 1),
+                        transform.matrix().get(1, 1),
+                        transform.matrix().get(2, 1));
+}
+
 }  // namespace cc