UI Language switch implemented by propagating LocaleChanged()

notification to all the views currently active. 
Before this CL, all views were recreated instead. That was very refactoring-unsafe.

Note, this is first part of the change. It prepares overall architecture means and can be committed first.
The other part contains implementation details and is here: http://codereview.chromium.org/1551029/show

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/1596023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@45057 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 40 insertions, 6 deletions

diff --git a/views/view.cc b/views/view.cc
index 3bdb2a2..d04ccec 100644
--- a/views/view.cc
+++ b/views/view.cc
@@ -651,9 +651,10 @@ void View::ThemeChanged() {
     GetChildViewAt(i)->ThemeChanged();
 }
 
-void View::LocaleChanged() {
+void View::NotifyLocaleChanged() {
+  LocaleChanged();
   for (int i = GetChildViewCount() - 1; i >= 0; --i)
-    GetChildViewAt(i)->LocaleChanged();
+    GetChildViewAt(i)->NotifyLocaleChanged();
 }
 
 #ifndef NDEBUG
diff --git a/views/view.h b/views/view.h
index d8177aa..bdf1b23 100644
--- a/views/view.h
+++ b/views/view.h
@@ -982,10 +982,8 @@ class View : public AcceleratorTarget {
   virtual void ThemeChanged();
 
   // Called when the locale has changed, overriding allows individual Views to
-  // update locale-dependent resources (strings, bitmaps) it may have cached
-  // internally. Subclasses that override this method must call the base class
-  // implementation to ensure child views are processed.
-  virtual void LocaleChanged();
+  // update locale-dependent strings.
+  virtual void LocaleChanged() { }
 
 #ifndef NDEBUG
   // Returns true if the View is currently processing a paint.
@@ -1125,6 +1123,10 @@ class View : public AcceleratorTarget {
     gfx::Point start_pt;
   };
 
+  // Propagates locale changed notification from the root view downside.
+  // Invokes LocaleChanged() for every view in the hierarchy.
+  virtual void NotifyLocaleChanged();
+
   // RootView invokes these. These in turn invoke the appropriate OnMouseXXX
   // method. If a drag is detected, DoDrag is invoked.
   bool ProcessMousePressed(const MouseEvent& e, DragInfo* drop_info);
diff --git a/views/widget/root_view.cc b/views/widget/root_view.cc
index 179d49d..3ea101c 100644
--- a/views/widget/root_view.cc
+++ b/views/widget/root_view.cc
@@ -241,6 +241,11 @@ void RootView::ThemeChanged() {
   View::ThemeChanged();
 }
 
+void RootView::NotifyLocaleChanged() {
+  // Propagate downside. Note that View::NotifyLocaleChanged() is private.
+  View::NotifyLocaleChanged();
+}
+
 /////////////////////////////////////////////////////////////////////////////
 //
 // RootView - event dispatch and propagation
diff --git a/views/widget/root_view.h b/views/widget/root_view.h
index 2d74b1f..aee0bf8 100644
--- a/views/widget/root_view.h
+++ b/views/widget/root_view.h
@@ -80,6 +80,10 @@ class RootView : public View,
   // hierarchy.
   virtual void ThemeChanged();
 
+  // Public API for broadcasting locale change notifications to this View
+  // hierarchy.
+  virtual void NotifyLocaleChanged();
+
   // The following event methods are overridden to propagate event to the
   // control tree
   virtual bool OnMousePressed(const MouseEvent& e);
diff --git a/views/widget/widget.h b/views/widget/widget.h
index b57a701..d4ddcfc 100644
--- a/views/widget/widget.h
+++ b/views/widget/widget.h
@@ -84,6 +84,10 @@ class Widget {
   static Widget* GetWidgetFromNativeView(gfx::NativeView native_view);
   static Widget* GetWidgetFromNativeWindow(gfx::NativeWindow native_window);
 
+  // Enumerates all windows pertaining to us and notifies their
+  // view hierarchies that the locale has changed.
+  static void NotifyLocaleChanged();
+
   // Initialize the Widget with a parent and an initial desired size.
   // |contents_view| is the view that will be the single child of RootView
   // within this Widget. As contents_view is inserted into RootView's tree,
diff --git a/views/widget/widget_gtk.cc b/views/widget/widget_gtk.cc
index d65ee99..20b0287 100644
--- a/views/widget/widget_gtk.cc
+++ b/views/widget/widget_gtk.cc
@@ -1388,4 +1388,17 @@ Widget* Widget::GetWidgetFromNativeWindow(gfx::NativeWindow native_window) {
   return NULL;
 }
 
+// static
+void Widget::NotifyLocaleChanged() {
+  GList *window_list = gtk_window_list_toplevels();
+  for (GList* element = window_list; element; element = g_list_next(element)) {
+    GtkWindow* window = GTK_WINDOW(element->data);
+    DCHECK(window);
+    RootView *root_view = FindRootView(window);
+    if (root_view)
+      root_view->NotifyLocaleChanged();
+  }
+  g_list_free(window_list);
+}
+
 }  // namespace views
diff --git a/views/widget/widget_win.cc b/views/widget/widget_win.cc
index 99e6395..84aece0 100644
--- a/views/widget/widget_win.cc
+++ b/views/widget/widget_win.cc
@@ -1331,4 +1331,9 @@ Widget* Widget::GetWidgetFromNativeWindow(gfx::NativeWindow native_window) {
   return Widget::GetWidgetFromNativeView(native_window);
 }
 
+// static
+void Widget::NotifyLocaleChanged() {
+  NOTIMPLEMENTED();
+}
+
 }  // namespace views