Disable VK overscroll for login/out-of-box.

ui/keyboard/keyboard_util.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_util.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
@@ skipping 27 matching lines @@
 
 base::LazyInstance<base::Time> g_keyboard_load_time_start =
     LAZY_INSTANCE_INITIALIZER;
 
 bool g_accessibility_keyboard_enabled = false;
 
 base::LazyInstance<GURL> g_override_content_url = LAZY_INSTANCE_INITIALIZER;
 
 bool g_touch_keyboard_enabled = false;
 
+bool g_keyboard_overscroll_override_enabled = false;
+
+bool g_keyboard_overscroll_enabled_override_value = true;

[kevers, 2014/05/21 13:56:11]

Feels a bit messy using 2 booleans here. Can we replace with a tri-valued
enumeration (NONE, ENABLED, DISABLED)?

[Nikita (slow), 2014/05/21 17:21:04]

Done.

+
 }  // namespace
 
 namespace keyboard {
 
 gfx::Rect DefaultKeyboardBoundsFromWindowBounds(
     const gfx::Rect& window_bounds) {
   // Initialize default keyboard height to 0. The keyboard window height should
   // only be set by window.resizeTo in virtual keyboard web contents. Otherwise,
   // the default height may conflict with the new height and causing some
   // strange animation issues. For keyboard usability experiments, a full screen
@@ skipping 45 matching lines @@
 }
 
 bool IsKeyboardUsabilityExperimentEnabled() {
   return CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kKeyboardUsabilityExperiment);
 }
 
 bool IsKeyboardOverscrollEnabled() {
   if (!IsKeyboardEnabled())
     return false;
+
   // Users of the accessibility on-screen keyboard are likely to be using mouse
   // input, which may interfere with overscrolling.
   if (g_accessibility_keyboard_enabled)
     return false;
+
+  // If overscroll enabled override is set, use it instead. Currently
+  // login / out-of-box disable keyboard overscroll. http://crbug.com/363635
+  if (g_keyboard_overscroll_override_enabled)
+    return g_keyboard_overscroll_enabled_override_value;
+
   if (CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kDisableVirtualKeyboardOverscroll)) {
     return false;
   }
   return true;
 }
 
+void SetKeyboardOverscrollEnabledOverrideValue(bool enabled) {
+  g_keyboard_overscroll_enabled_override_value = enabled;
+}
+
+void SetKeyboardOverscrollOverrideEnabled(bool enabled) {
+  g_keyboard_overscroll_override_enabled = enabled;
+}
+
 bool IsInputViewEnabled() {
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnableInputView))
     return true;
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kDisableInputView))
     return false;
   // Default value if no command line flags specified.
   return true;
 }
 
 bool InsertText(const base::string16& text, aura::Window* root_window) {
@@ skipping 204 matching lines @@
 }
 
 void LogKeyboardControlEvent(KeyboardControlEvent event) {
   UMA_HISTOGRAM_ENUMERATION(
       "VirtualKeyboard.KeyboardControlEvent",
       event,
       keyboard::KEYBOARD_CONTROL_MAX);
 }
 
 }  // namespace keyboard