Implements computation of touch calibration transform using user provided data

ash/touch/touch_transformer_controller.h

Index: ash/touch/touch_transformer_controller.h
diff --git a/ash/touch/touch_transformer_controller.h b/ash/touch/touch_transformer_controller.h
index 640fcbb8c8f499de202b8db3080bafbbe691e33c..cfebb79e4a78acf8d4a79b539e8e551722c15135 100644
--- a/ash/touch/touch_transformer_controller.h
+++ b/ash/touch/touch_transformer_controller.h
@@ -35,6 +35,10 @@ class ASH_EXPORT TouchTransformerController
   void OnDisplaysInitialized() override;
   void OnDisplayConfigurationChanged() override;
 
+  // During touch calibration we remove any kind of transform that is being
+  // applied to the touch input's location.

[kylechar, 2016/12/19 20:00:21]

This also updates the transforms right?

[malaykeshav, 2016/12/20 09:56:04]

No. This only sets the TouchTransformerController in a state that returns an
empty transform.
This is required during calibration. We want raw touch inputs that are not
transformed in their local screen space. 

[kylechar, 2016/12/20 17:41:28]

What does the call to UpdateTouchTransformer() do then? It seems like it would
set empty transforms if is_calibrating and properly sets transforms if
!is_calibrating.

[malaykeshav, 2016/12/20 19:16:55]

Correct. When the calibration is under process (See
https://drive.google.com/a/google.com/file/d/0B_WkX8bSkoT1QVR0WFJYdUY2SmZTdWd...
) we want no transform to be applied to the touch inputs since we are trying to
collect data that computes the new calibrated transform.

+  void SetForCalibration(bool is_calibrating);
+
  private:
   FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,

[kylechar, 2016/12/19 20:00:21]

Would it just be simpler to make TouchTransformerControllerTest a friend class
at this point?

[malaykeshav, 2016/12/20 09:56:05]

Done

[kylechar, 2016/12/20 17:41:28]

This wasn't done?

[malaykeshav, 2016/12/20 19:16:55]

I was unable to friend class TouchTransformerControllerTest for some reason. The
compiler throws private function access error. I will try again when I have
access to corp network tmrw morning. 
Resolving rest of the comments atm.

[malaykeshav, 2016/12/21 05:49:42]

Done

                            MirrorModeLetterboxing);
@@ -43,6 +47,19 @@ class ASH_EXPORT TouchTransformerController
   FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest, SoftwareMirrorMode);
   FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest, ExtendedMode);
   FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest, TouchRadiusScale);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest, OzoneTrasnlation);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           AccurateUserTouchCalibration);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           ErrorProneUserTouchCalibration);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           ResolutionChangeUserTouchCalibration);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           DifferentBoundsUserTouchCalibration);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           LetterboxingUserTouchCalibration);
+  FRIEND_TEST_ALL_PREFIXES(TouchTransformerControllerTest,
+                           PillarBoxingUserTouchCalibration);
 
   // Returns a transform that will be used to change an event's location from
   // the touchscreen's coordinate system into |display|'s coordinate system.
@@ -82,6 +99,8 @@ class ASH_EXPORT TouchTransformerController
       const display::ManagedDisplayInfo& touch_display,
       const display::ManagedDisplayInfo& target_display) const;
 
+  bool is_calibrating_ = false;
+
   DISALLOW_COPY_AND_ASSIGN(TouchTransformerController);
 };