Add UMA stats for pen palette

ash/common/system/chromeos/palette/mock_palette_tool_delegate.h

Index: ash/common/system/chromeos/palette/mock_palette_tool_delegate.h
diff --git a/ash/common/system/chromeos/palette/mock_palette_tool_delegate.h b/ash/common/system/chromeos/palette/mock_palette_tool_delegate.h
index 556b61d8c0c8359e2d9c307c2f1546002994ec6c..179e2b8d0ebd17f33f252bc4aca2ffd2b0e348d5 100644
--- a/ash/common/system/chromeos/palette/mock_palette_tool_delegate.h
+++ b/ash/common/system/chromeos/palette/mock_palette_tool_delegate.h
@@ -20,6 +20,8 @@ class MockPaletteToolDelegate : public PaletteTool::Delegate {
   MOCK_METHOD1(DisableTool, void(PaletteToolId tool_id));
   MOCK_METHOD0(HidePalette, void());
   MOCK_METHOD0(GetWindow, WmWindow*());
+  MOCK_METHOD1(RecordPaletteOptionsUsage, void(PaletteTrayOptions option));
+  MOCK_METHOD1(RecordPaletteModeCancellation, void(PaletteModeCancelType type));
 };
 
 }  // namespace ash