Fix display switching for extended displays.

Currently when we switch between displays with extended displays turned on, the sequence is,
Mirrored -> Extended -> Extended (reversed) -> Mirrorer.

Change this to switch only between extended and mirrored displays if the extended display flag is enabled,
i.e.,
Mirrorer -> Extended -> Mirrored.


R=oshima@chromium.org
BUG=137727
TEST=Tested on a ChromeOS device with a secondary display to confirm that the inteded sequence is followed on switching displays.


Review URL: https://chromiumcodereview.appspot.com/10829026

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@148842 0039d316-1c4b-4281-b951-d872f2087c98

ash/accelerators/accelerator_controller.cc

@@ -407,7 +407,8 @@ bool AcceleratorController::PerformAction(int action,
     case TOGGLE_SPOKEN_FEEDBACK:
       return HandleToggleSpokenFeedback();
     case CYCLE_DISPLAY_MODE:
-      ash::Shell::GetInstance()->output_configurator()->CycleDisplayMode();
+      ash::Shell::GetInstance()->output_configurator()->CycleDisplayMode(
+          internal::DisplayController::IsExtendedDesktopEnabled());
       return true;
 #endif
     case OPEN_FEEDBACK_PAGE:

chromeos/display/output_configurator.cc

@@ -659,22 +659,32 @@ State OutputConfigurator::InferCurrentState(Display* display,
   return state;
 }
 
-bool OutputConfigurator::CycleDisplayMode() {
+bool OutputConfigurator::CycleDisplayMode(bool extended_desktop_enabled) {
   VLOG(1) << "CycleDisplayMode";
   bool did_change = false;
+
   if (is_running_on_chrome_os_) {
     // Rules:
     // - if there are 0 or 1 displays, do nothing and return false.
     // - use y-coord of CRTCs to determine if we are mirror, primary-first, or
     // secondary-first.  The cycle order is:
     //   mirror->primary->secondary->mirror.
+    // Note: If the extended desktop is enabled, the cycle order becomes,
+    // mirror->extended->mirror
     State new_state = STATE_INVALID;
     switch (output_state_) {
       case STATE_DUAL_MIRROR:
         new_state = STATE_DUAL_PRIMARY_ONLY;
         break;
       case STATE_DUAL_PRIMARY_ONLY:
-        new_state = STATE_DUAL_SECONDARY_ONLY;
+        if (extended_desktop_enabled) {
+          if (mirror_supported_)
+            new_state = STATE_DUAL_MIRROR;
+          else
+            new_state = STATE_INVALID;
+        } else {
+          new_state = STATE_DUAL_SECONDARY_ONLY;
+        }
         break;
       case STATE_DUAL_SECONDARY_ONLY:
         new_state = mirror_supported_ ?

chromeos/display/output_configurator.h

@@ -65,7 +65,7 @@ class CHROMEOS_EXPORT OutputConfigurator : public MessageLoop::Dispatcher {
   // Called when the user hits ctrl-F4 to request a display mode change.
   // This method should only return false if it was called in a single-head or
   // headless mode.
-  bool CycleDisplayMode();
+  bool CycleDisplayMode(bool extended_desktop_enabled);
 
   // Called when powerd notifies us that some set of displays should be turned
   // on or off.  This requires enabling or disabling the CRTC associated with