Fix display switching for extended displays.

chromeos/display/output_configurator.cc

Index: chromeos/display/output_configurator.cc
diff --git a/chromeos/display/output_configurator.cc b/chromeos/display/output_configurator.cc
index 60013092234cbe9ba6612111b451f5159126c88e..4f8c78904a493dfc91ec73514be9670c95fc4a30 100644
--- a/chromeos/display/output_configurator.cc
+++ b/chromeos/display/output_configurator.cc
@@ -16,6 +16,7 @@
 #undef Status
 #undef RootWindow
 
+#include "ash/display/display_controller.h"
 #include "base/chromeos/chromeos_version.h"
 #include "base/logging.h"
 #include "base/message_pump_aurax11.h"
@@ -662,6 +663,19 @@ State OutputConfigurator::InferCurrentState(Display* display,
 bool OutputConfigurator::CycleDisplayMode() {
   VLOG(1) << "CycleDisplayMode";
   bool did_change = false;
+
+  // The next state to go into if the current state is dual primary.
+  State next_state_from_dual_primary = STATE_DUAL_SECONDARY_ONLY;
+  if (ash::internal::DisplayController::IsExtendedDesktopEnabled()) {

[oshima, 2012/07/25 23:44:20]

/chromeos can't depend on /ash.Can you let ash switch the mode in output
configurator instead? (like SetEnbableSecondaryOnly())

[rkc, 2012/07/25 23:59:37]

Done.

+    if (mirror_supported_) {
+      next_state_from_dual_primary = STATE_DUAL_MIRROR;
+    } else {
+      // In case mirror is not supported, stay in the
+      // extended desktop primary display.
+      next_state_from_dual_primary = STATE_INVALID;
+    }
+  }
+
   if (is_running_on_chrome_os_) {
     // Rules:
     // - if there are 0 or 1 displays, do nothing and return false.
@@ -674,7 +688,7 @@ bool OutputConfigurator::CycleDisplayMode() {
         new_state = STATE_DUAL_PRIMARY_ONLY;
         break;
       case STATE_DUAL_PRIMARY_ONLY:
-        new_state = STATE_DUAL_SECONDARY_ONLY;
+        new_state = next_state_from_dual_primary;
         break;
       case STATE_DUAL_SECONDARY_ONLY:
         new_state = mirror_supported_ ?