Do not automatically maximize the window if the maximized bounds can be controlled by the client.

ash/common/wm/maximize_mode/maximize_mode_window_manager.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/common/wm/maximize_mode/maximize_mode_window_manager.h"
 
 #include "ash/common/ash_switches.h"
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/shell_window_ids.h"
 #include "ash/common/wm/maximize_mode/maximize_mode_event_handler.h"
@@ skipping 210 matching lines @@
 
   // Windows with the always-on-top property should be free-floating and thus
   // not managed by us.
   if (window->IsAlwaysOnTop())
     return false;
 
   // Windows in the dock should not be managed by us.
   if (window->GetWindowState()->IsDocked())
     return false;
 
+  // If the changing bounds in the maximized/fullscreen is allowed, then
+  // let the client manage it even in maximized mode.
+  if (window->GetWindowState()->allow_set_bounds_in_maximized())
+    return false;
+
   return window->GetType() == ui::wm::WINDOW_TYPE_NORMAL;
 }
 
 void MaximizeModeWindowManager::AddWindowCreationObservers() {
   DCHECK(observed_container_windows_.empty());
   // Observe window activations/creations in the default containers on all root
   // windows.
   for (WmWindow* root : WmShell::Get()->GetAllRootWindows()) {
     WmWindow* default_container =
         root->GetChildByShellWindowId(kShellWindowId_DefaultContainer);
@@ skipping 36 matching lines @@
   for (WmWindow* root : WmShell::Get()->GetAllRootWindows()) {
     WmRootWindowController* controller = root->GetRootWindowController();
     WmWindow* default_container =
         root->GetChildByShellWindowId(kShellWindowId_DefaultContainer);
     controller->SetMaximizeBackdropDelegate(base::WrapUnique(
         enable ? new WorkspaceBackdropDelegate(default_container) : nullptr));
   }
 }
 
 }  // namespace ash