Fixed the Touchscreen.TouchEventsEnabled histogram to record the correct values on X11 and Ozone ba…

ui/events/devices/device_data_manager.cc

Index: ui/events/devices/device_data_manager.cc
diff --git a/ui/events/devices/device_data_manager.cc b/ui/events/devices/device_data_manager.cc
index e725736df3923ad538e69795a0d10fd586c5e87b..8633ddf9dc513b4768c85ea6e2937e21f51b09b8 100644
--- a/ui/events/devices/device_data_manager.cc
+++ b/ui/events/devices/device_data_manager.cc
@@ -35,7 +35,8 @@ DeviceDataManager::~DeviceDataManager() {
 DeviceDataManager* DeviceDataManager::instance() { return instance_; }
 
 void DeviceDataManager::set_instance(DeviceDataManager* instance) {
-  CHECK(!instance_) << "Can not set multiple instances of DeviceDataManager";
+  CHECK(!instance || !instance_)

[Alexei Svitkine (slow), 2015/07/07 22:00:59]

Nit: I think this should be a DCHECK().

[bruthig, 2015/07/08 20:29:52]

Done.

+      << "Can not set multiple instances of DeviceDataManager";

[sadrul, 2015/07/07 22:04:39]

Have separate DCHECK()s with the right message instead? "Cannot set multiple ...
" and "Must be non-null"

[bruthig, 2015/07/08 20:29:52]

Actually the logic is, 'instance' can be null, or 'instance_' cannot be null. 
The tests need to be able to explicitly reset the instance to something else. I
have updated the message though.  WDYT?

   instance_ = instance;
 }
 
@@ -46,6 +47,7 @@ void DeviceDataManager::CreateInstance() {
 
   set_instance(new DeviceDataManager());
 
+  // TODO(bruthig): Replace the DeleteInstance callbacks with explicit calls.
   base::AtExitManager::RegisterTask(base::Bind(DeleteInstance));
 }
 
@@ -132,9 +134,7 @@ void DeviceDataManager::OnTouchscreenDevicesUpdated(
     return;
   }
   touchscreen_devices_ = devices;
-  FOR_EACH_OBSERVER(InputDeviceEventObserver,
-                    observers_,
-                    OnTouchscreenDeviceConfigurationChanged());
+  NotifyObserversTouchscreenDeviceConfigurationChanged();
 }
 
 void DeviceDataManager::OnKeyboardDevicesUpdated(
@@ -147,9 +147,7 @@ void DeviceDataManager::OnKeyboardDevicesUpdated(
     return;
   }
   keyboard_devices_ = devices;
-  FOR_EACH_OBSERVER(InputDeviceEventObserver,
-                    observers_,
-                    OnKeyboardDeviceConfigurationChanged());
+  NotifyObserversKeyboardDeviceConfigurationChanged();
 }
 
 void DeviceDataManager::OnMouseDevicesUpdated(
@@ -162,9 +160,7 @@ void DeviceDataManager::OnMouseDevicesUpdated(
     return;
   }
   mouse_devices_ = devices;
-  FOR_EACH_OBSERVER(InputDeviceEventObserver,
-                    observers_,
-                    OnMouseDeviceConfigurationChanged());
+  NotifyObserversMouseDeviceConfigurationChanged();
 }
 
 void DeviceDataManager::OnTouchpadDevicesUpdated(
@@ -177,17 +173,39 @@ void DeviceDataManager::OnTouchpadDevicesUpdated(
     return;
   }
   touchpad_devices_ = devices;
-  FOR_EACH_OBSERVER(InputDeviceEventObserver,
-                    observers_,
-                    OnTouchpadDeviceConfigurationChanged());
+  NotifyObserversTouchpadDeviceConfigurationChanged();
 }
 
 void DeviceDataManager::OnDeviceListsComplete() {
   if (!device_lists_complete_) {
     device_lists_complete_ = true;
+    NotifyObserversDeviceListsComplete();
+  }
+}
+
+void DeviceDataManager::NotifyObserversTouchscreenDeviceConfigurationChanged() {
+  FOR_EACH_OBSERVER(InputDeviceEventObserver, observers_,
+                    OnTouchscreenDeviceConfigurationChanged());
+}
+
+void DeviceDataManager::NotifyObserversKeyboardDeviceConfigurationChanged() {
+  FOR_EACH_OBSERVER(InputDeviceEventObserver, observers_,
+                    OnKeyboardDeviceConfigurationChanged());
+}
+
+void DeviceDataManager::NotifyObserversMouseDeviceConfigurationChanged() {
+  FOR_EACH_OBSERVER(InputDeviceEventObserver, observers_,
+                    OnMouseDeviceConfigurationChanged());
+}
+
+void DeviceDataManager::NotifyObserversTouchpadDeviceConfigurationChanged() {
+  FOR_EACH_OBSERVER(InputDeviceEventObserver, observers_,
+                    OnTouchpadDeviceConfigurationChanged());
+}
+
+void DeviceDataManager::NotifyObserversDeviceListsComplete() {
     FOR_EACH_OBSERVER(InputDeviceEventObserver, observers_,
                       OnDeviceListsComplete());
-  }
 }
 
 void DeviceDataManager::AddObserver(InputDeviceEventObserver* observer) {