Lock rotation when screen is manually rotated.

ash/display/display_info.h

Index: ash/display/display_info.h
diff --git a/ash/display/display_info.h b/ash/display/display_info.h
index 62f9210078b609c72d5b9c153a9bc54b494db92e..008f7ab3e5f8c80714fec307f0786107aae0dbcc 100644
--- a/ash/display/display_info.h
+++ b/ash/display/display_info.h
@@ -5,6 +5,7 @@
 #ifndef ASH_DISPLAY_DISPLAY_INFO_H_
 #define ASH_DISPLAY_DISPLAY_INFO_H_
 
+#include <map>
 #include <string>
 #include <vector>
 
@@ -95,8 +96,15 @@ class ASH_EXPORT DisplayInfo {
   // actual overscan automatically, but used in the message.
   bool has_overscan() const { return has_overscan_; }
 
-  void set_rotation(gfx::Display::Rotation rotation) { rotation_ = rotation; }
-  gfx::Display::Rotation rotation() const { return rotation_; }
+  // Returns the last rotation set through either user actions, or the
+  // accelerometer. The current active rotation of the display can be found by
+  // calling |rotation()|.
+  gfx::Display::Rotation GetRotation(ui::RotationSource source);

[flackr, 2014/05/16 16:00:22]

Do we ever want to get the last saved accelerometer rotation? I wonder if just
having rotation_ and something like saved_rotation_ would be sufficient?

[jonross, 2014/05/20 15:24:30]

A few potential uses:
  - Testing
  - Saving as a preference in combination with rotation lock. So that a reboot
of device into maximize mode preserves both orientation and the lock state.

+
+  // Updates the rotation for the given source, and also sets the current
+  // rotation.
+  void SetRotation(gfx::Display::Rotation rotation, ui::RotationSource source);
+  gfx::Display::Rotation rotation() const { return current_rotation_; }
 
   void set_touch_support(gfx::Display::TouchSupport support) {
     touch_support_ = support;
@@ -201,7 +209,8 @@ class ASH_EXPORT DisplayInfo {
   int64 id_;
   std::string name_;
   bool has_overscan_;
-  gfx::Display::Rotation rotation_;
+  gfx::Display::Rotation current_rotation_;
+  std::map<ui::RotationSource, gfx::Display::Rotation> rotations_;
   gfx::Display::TouchSupport touch_support_;
 
   // If the display is also a touch device, it will have a positive