From d102d04d237761cb414e253504e8bee4a0decd36 Mon Sep 17 00:00:00 2001
From: sky <sky@chromium.org>
Date: Tue, 30 Sep 2014 17:43:06 -0700
Subject: [PATCH] Fixes two bugs in causing demo_launcher to crash

. MoveToFront/Back triggered a DCHECK. Made them early out if view
  already in position.
. Called WindowManagerApp::InitFocus so that we don't crash when
  WM::SetFocus is called.

BUG=none
TEST=none
R=ben@chromium.org

Review URL: https://codereview.chromium.org/615233003

Cr-Commit-Position: refs/heads/master@{#297559}
---
 mojo/examples/window_manager/BUILD.gn         |  1 +
 mojo/examples/window_manager/DEPS             |  1 +
 .../examples/window_manager/window_manager.cc | 62 +++++++++++++++++++
 mojo/mojo_examples.gypi                       |  1 +
 .../public/cpp/view_manager/lib/view.cc       |  4 ++
 5 files changed, 69 insertions(+)

diff --git a/mojo/examples/window_manager/BUILD.gn b/mojo/examples/window_manager/BUILD.gn
index 2d55368b8c8b5..8c89c04b7bae8 100644
--- a/mojo/examples/window_manager/BUILD.gn
+++ b/mojo/examples/window_manager/BUILD.gn
@@ -42,6 +42,7 @@ shared_library("window_manager") {
     "//ui/gl",
     "//ui/resources",
     "//ui/views",
+    "//ui/wm",
   ]
 }
 
diff --git a/mojo/examples/window_manager/DEPS b/mojo/examples/window_manager/DEPS
index bfc0d9fa05897..372b6a82677cc 100644
--- a/mojo/examples/window_manager/DEPS
+++ b/mojo/examples/window_manager/DEPS
@@ -3,4 +3,5 @@ include_rules = [
   "+ui/events",
   "+ui/gfx",
   "+ui/views",
+  "+ui/wm/core",
 ]
diff --git a/mojo/examples/window_manager/window_manager.cc b/mojo/examples/window_manager/window_manager.cc
index 992407182f392..83c96ce33cbbf 100644
--- a/mojo/examples/window_manager/window_manager.cc
+++ b/mojo/examples/window_manager/window_manager.cc
@@ -29,6 +29,7 @@
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
 #include "ui/gfx/geometry/size_conversions.h"
+#include "ui/wm/core/focus_rules.h"
 
 #if defined CreateWindow
 #undef CreateWindow
@@ -45,6 +46,64 @@ const int kBorderInset = 25;
 const int kControlPanelWidth = 200;
 const int kTextfieldHeight = 25;
 
+class WMFocusRules : public wm::FocusRules {
+ public:
+  WMFocusRules(mojo::WindowManagerApp* window_manager_app,
+               mojo::View* window_container)
+      : window_container_(window_container),
+        window_manager_app_(window_manager_app) {}
+  virtual ~WMFocusRules() {}
+
+ private:
+  // Overridden from wm::FocusRules:
+  virtual bool IsToplevelWindow(aura::Window* window) const override {
+    return mojo::WindowManagerApp::GetViewForWindow(window)->parent() ==
+        window_container_;
+  }
+  virtual bool CanActivateWindow(aura::Window* window) const override {
+    return mojo::WindowManagerApp::GetViewForWindow(window)->parent() ==
+        window_container_;
+  }
+  virtual bool CanFocusWindow(aura::Window* window) const override {
+    return true;
+  }
+  virtual aura::Window* GetToplevelWindow(aura::Window* window) const override {
+    mojo::View* view = mojo::WindowManagerApp::GetViewForWindow(window);
+    while (view->parent() != window_container_) {
+      view = view->parent();
+      // Unparented hierarchy, there is no "top level" window.
+      if (!view)
+        return NULL;
+    }
+
+    return window_manager_app_->GetWindowForViewId(view->id());
+  }
+  virtual aura::Window* GetActivatableWindow(
+      aura::Window* window) const override {
+    return GetToplevelWindow(window);
+  }
+  virtual aura::Window* GetFocusableWindow(
+      aura::Window* window) const override {
+    return window;
+  }
+  virtual aura::Window* GetNextActivatableWindow(
+      aura::Window* ignore) const override {
+    aura::Window* activatable = GetActivatableWindow(ignore);
+    const aura::Window::Windows& children = activatable->parent()->children();
+    for (aura::Window::Windows::const_reverse_iterator it = children.rbegin();
+         it != children.rend(); ++it) {
+      if (*it != ignore)
+        return *it;
+    }
+    return NULL;
+  }
+
+  mojo::View* window_container_;
+  mojo::WindowManagerApp* window_manager_app_;
+
+  DISALLOW_COPY_AND_ASSIGN(WMFocusRules);
+};
+
 }  // namespace
 
 class WindowManagerConnection : public InterfaceImpl<IWindowManager> {
@@ -385,6 +444,9 @@ class WindowManager
     root->AddObserver(root_layout_manager_.get());
 
     window_manager_app_->host()->window()->AddPreTargetHandler(this);
+
+    window_manager_app_->InitFocus(new WMFocusRules(window_manager_app_.get(),
+                                                    view));
   }
   virtual void OnViewManagerDisconnected(ViewManager* view_manager) OVERRIDE {
     DCHECK_EQ(view_manager_, view_manager);
diff --git a/mojo/mojo_examples.gypi b/mojo/mojo_examples.gypi
index 359dfc9ec97e5..b863a39d4678f 100644
--- a/mojo/mojo_examples.gypi
+++ b/mojo/mojo_examples.gypi
@@ -668,6 +668,7 @@
             '../ui/resources/ui_resources.gyp:ui_resources',
             '../ui/resources/ui_resources.gyp:ui_test_pak',
             '../ui/views/views.gyp:views',
+            '../ui/wm/wm.gyp:wm',
             'mojo_base.gyp:mojo_application_chromium',
             'mojo_base.gyp:mojo_cpp_bindings',
             'mojo_base.gyp:mojo_utility',
diff --git a/mojo/services/public/cpp/view_manager/lib/view.cc b/mojo/services/public/cpp/view_manager/lib/view.cc
index c3bf63a750824..82b6d11e9e981 100644
--- a/mojo/services/public/cpp/view_manager/lib/view.cc
+++ b/mojo/services/public/cpp/view_manager/lib/view.cc
@@ -256,10 +256,14 @@ void View::RemoveChild(View* child) {
 }
 
 void View::MoveToFront() {
+  if (!parent_ || parent_->children_.back() == this)
+    return;
   Reorder(parent_->children_.back(), ORDER_DIRECTION_ABOVE);
 }
 
 void View::MoveToBack() {
+  if (!parent_ || parent_->children_.front() == this)
+    return;
   Reorder(parent_->children_.front(), ORDER_DIRECTION_BELOW);
 }