Fix mojo build on android.

Android stl library has bugs related to std::set ->
https://code.google.com/p/android/issues/detail?id=69153

This change allow this code to compile on android.

R=viettrungluu@chromium.org

Review URL: https://codereview.chromium.org/335903004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278657 0039d316-1c4b-4281-b951-d872f2087c98

mojo/services/public/cpp/view_manager/tests/view_manager_unittest.cc

@@ -199,7 +199,7 @@ class DestructionObserver : public NodeObserver, public ViewObserver {
       NodeObserver::DispositionChangePhase phase) OVERRIDE {
     if (phase != NodeObserver::DISPOSITION_CHANGED)
       return;
-    std::set<Id>::const_iterator it = nodes_->find(node->id());
+    std::set<Id>::iterator it = nodes_->find(node->id());
     if (it != nodes_->end())
       nodes_->erase(it);
     if (CanQuit())
@@ -212,7 +212,7 @@ class DestructionObserver : public NodeObserver, public ViewObserver {
       ViewObserver::DispositionChangePhase phase) OVERRIDE {
     if (phase != ViewObserver::DISPOSITION_CHANGED)
       return;
-    std::set<Id>::const_iterator it = views_->find(view->id());
+    std::set<Id>::iterator it = views_->find(view->id());
     if (it != views_->end())
       views_->erase(it);
     if (CanQuit())