Fixed ui::TouchEvent rotation angle out-of-bound issue.

ui/events/event.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_EVENTS_EVENT_H_
 #define UI_EVENTS_EVENT_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/event_types.h"
@@ skipping 532 matching lines @@
   }
 
  protected:
   void set_radius(float radius_x, float radius_y) {
     radius_x_ = radius_x;
     radius_y_ = radius_y;
   }
 
   void set_rotation_angle(float rotation_angle) {
     rotation_angle_ = rotation_angle;
+    fixRotationAngle();
   }
 
   void set_force(float force) { force_ = force; }
 
  private:
   // The identity (typically finger) of the touch starting at 0 and incrementing
   // for each separable additional touch that the hardware can detect.
   const int touch_id_;
 
   // A unique identifier for the touch event.
   const uint64 unique_event_id_;
 
   // Radius of the X (major) axis of the touch ellipse. 0.0 if unknown.
   float radius_x_;
 
   // Radius of the Y (minor) axis of the touch ellipse. 0.0 if unknown.
   float radius_y_;
 
   // Angle of the major axis away from the X axis. Default 0.0.
   float rotation_angle_;
 
   // Force (pressure) of the touch. Normalized to be [0, 1]. Default to be 0.0.
   float force_;
 
   // Whether the (unhandled) touch event will produce a scroll event (e.g., a
   // touchmove that exceeds the platform slop region, or a touchend that
   // causes a fling). Defaults to false.
   bool may_cause_scrolling_;
+
+  // Adjusts rotation_angle_ to within the spec limits:
+  // https://dvcs.w3.org/hg/webevents/raw-file/default/touchevents.html

[tdresser, 2015/01/16 20:29:52]

As we're in the ui layer here, I don't think we want to reference web specific
requirements.

Just state that we ensure the rotation angle is between 0 and 90.

+  void fixRotationAngle();
 };
 
 // An interface that individual platforms can use to store additional data on
 // KeyEvent.
 //
 // Currently only used in mojo.
 class EVENTS_EXPORT ExtendedKeyEventData {
  public:
   virtual ~ExtendedKeyEventData() {}
 
@@ skipping 282 matching lines @@
 
   const GestureEventDetails& details() const { return details_; }
 
  private:
   GestureEventDetails details_;
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_EVENT_H_