ash: Rename LauncherIconObserver to ShelfIconObserver.

ash/launcher/launcher.h

Index: ash/launcher/launcher.h
diff --git a/ash/launcher/launcher.h b/ash/launcher/launcher.h
index 693f137b4265ebafe1fe24831577dfd08cb11b41..5c663b4968797a2982baca31c89a654499bfeb52 100644
--- a/ash/launcher/launcher.h
+++ b/ash/launcher/launcher.h
@@ -41,9 +41,9 @@ namespace test {
 class LauncherTestAPI;
 }
 
-class LauncherIconObserver;
 class LauncherDelegate;
 class LauncherModel;
+class ShelfIconObserver;
 class ShelfWidget;
 
 class ASH_EXPORT Launcher {
@@ -82,8 +82,8 @@ class ASH_EXPORT Launcher {
   // Cycles the window focus linearly over the current launcher items.
   void CycleWindowLinear(CycleDirection direction);
 
-  void AddIconObserver(LauncherIconObserver* observer);
-  void RemoveIconObserver(LauncherIconObserver* observer);
+  void AddIconObserver(ShelfIconObserver* observer);
+  void RemoveIconObserver(ShelfIconObserver* observer);
 
   // Returns true if the Launcher is showing a context menu.
   bool IsShowingMenu() const;