Disable pinch-to-zoom gesture on virtual keyboard

ui/keyboard/keyboard_controller.cc

 // Copyright (c) 2013 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 "ui/keyboard/keyboard_controller.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 170 matching lines @@
   input_method_ = ui_->GetInputMethod();
   input_method_->AddObserver(this);
   ui_->SetController(this);
 }
 
 KeyboardController::~KeyboardController() {
   if (container_) {
     if (container_->GetRootWindow())
       container_->GetRootWindow()->RemoveObserver(this);
     container_->RemoveObserver(this);
+    container_->RemovePreTargetHandler(&event_filter_);
   }
   if (input_method_)
     input_method_->RemoveObserver(this);
   for (KeyboardControllerObserver& observer : observer_list_)
     observer.OnKeyboardClosed();
   ui_->SetController(nullptr);
 }
 
 // static
 void KeyboardController::ResetInstance(KeyboardController* controller) {
   if (instance_ && instance_ != controller)
     delete instance_;
   instance_ = controller;
 }
 
 // static
 KeyboardController* KeyboardController::GetInstance() {
   return instance_;
 }
 
 aura::Window* KeyboardController::GetContainerWindow() {
   if (!container_.get()) {
     container_.reset(new aura::Window(new KeyboardWindowDelegate()));
     container_->SetName("KeyboardContainer");
     container_->set_owned_by_parent(false);
     container_->Init(ui::LAYER_NOT_DRAWN);
     container_->AddObserver(this);
     container_->SetLayoutManager(new KeyboardLayoutManager(this));
+    container_->AddPreTargetHandler(&event_filter_);
   }
   return container_.get();
 }
 
 void KeyboardController::NotifyKeyboardBoundsChanging(
     const gfx::Rect& new_bounds) {
   current_keyboard_bounds_ = new_bounds;
   if (ui_->HasKeyboardWindow() && ui_->GetKeyboardWindow()->IsVisible()) {
     for (KeyboardControllerObserver& observer : observer_list_)
       observer.OnKeyboardBoundsChanging(new_bounds);
@@ skipping 287 matching lines @@
     int keyboard_height = GetContainerWindow()->bounds().height();
     const gfx::Rect& root_bounds = container_->GetRootWindow()->bounds();
     gfx::Rect new_bounds = root_bounds;
     new_bounds.set_y(root_bounds.height() - keyboard_height);
     new_bounds.set_height(keyboard_height);
     GetContainerWindow()->SetBounds(new_bounds);
   }
 }
 
 }  // namespace keyboard