Fixing caps lock problems under ChromeOS where the tray does not properly follow the real caps lock…

chromeos/ime/xkeyboard.cc

Index: chromeos/ime/xkeyboard.cc
diff --git a/chromeos/ime/xkeyboard.cc b/chromeos/ime/xkeyboard.cc
index b2f55f14443e77a403ce47d27889b11c3a7fc658..4d8df51d79a2cf262e3478c83a68d39d8f0eec25 100644
--- a/chromeos/ime/xkeyboard.cc
+++ b/chromeos/ime/xkeyboard.cc
@@ -117,6 +117,10 @@ class XKeyboardImpl : public XKeyboard {
   XKeyboardImpl();
   virtual ~XKeyboardImpl() {}
 
+  // Adds/removes observer.
+  virtual void AddObserver(Observer* observer) OVERRIDE;
+  virtual void RemoveObserver(Observer* observer) OVERRIDE;
+
   // Overridden from XKeyboard:
   virtual bool SetCurrentKeyboardLayoutByName(
       const std::string& layout_name) OVERRIDE;
@@ -169,6 +173,8 @@ class XKeyboardImpl : public XKeyboard {
 
   base::WeakPtrFactory<XKeyboardImpl> weak_factory_;
 
+  ObserverList<Observer> observers_;
+
   DISALLOW_COPY_AND_ASSIGN(XKeyboardImpl);
 };
 
@@ -193,6 +199,14 @@ XKeyboardImpl::XKeyboardImpl()
   current_caps_lock_status_ = CapsLockIsEnabled();
 }
 
+void XKeyboardImpl::AddObserver(XKeyboard::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void XKeyboardImpl::RemoveObserver(XKeyboard::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
 unsigned int XKeyboardImpl::GetNumLockMask() {
   DCHECK(thread_checker_.CalledOnValidThread());
   static const unsigned int kBadMask = 0;
@@ -379,6 +393,10 @@ bool XKeyboardImpl::SetAutoRepeatRate(const AutoRepeatRate& rate) {
 
 void XKeyboardImpl::SetCapsLockEnabled(bool enable_caps_lock) {
   SetLockedModifiers(enable_caps_lock);
+  if (current_caps_lock_status_ != enable_caps_lock) {

[sadrul, 2014/04/10 01:16:45]

Calling SetLockedModifiers() will have changed current_caps_lock_status_ to be
the same as enable_caps_lock. Do you want to do this check before calling
SetLockedModifiers()? (or alternatively, store current_caps_lock_status_ before
calling SetLockedModifiers(), and compare with that)

[Mr4D (OOO till 08-26), 2014/04/10 14:16:02]

Good catch. In deed. I wonder why my test on the device seem to have worked
yesterday. Done!

+    FOR_EACH_OBSERVER(XKeyboard::Observer, observers_,
+                      OnCapsLockChanged(enable_caps_lock));
+  }
 }
 
 bool XKeyboardImpl::SetCurrentKeyboardLayoutByName(