Add an experimental keyboard lock, where Esc must be held to exit.

chrome/browser/ui/exclusive_access/exclusive_access_manager.cc

Index: chrome/browser/ui/exclusive_access/exclusive_access_manager.cc
diff --git a/chrome/browser/ui/exclusive_access/exclusive_access_manager.cc b/chrome/browser/ui/exclusive_access/exclusive_access_manager.cc
index 666d11e6970660990014e60c2a88d65f567d018b..29ecf1687cf6c3cf49ff552fbdecc003fa655d4a 100644
--- a/chrome/browser/ui/exclusive_access/exclusive_access_manager.cc
+++ b/chrome/browser/ui/exclusive_access/exclusive_access_manager.cc
@@ -19,11 +19,19 @@
 
 using content::WebContents;
 
+namespace {
+
+// Time in seconds required to hold the Esc key in order to exit full screen.
+const double kDurationToHoldEscapeToExitFullscreen = 1.5;

[Matt Giuca, 2016/03/21 00:36:07]

I think this should be in c/b/u/exclusive_access/exclusive_access_bubble, along
with all of the other timing constants. And it should be int, in ms.

[dominickn, 2016/03/21 21:58:04]

That means a) pulling in exclusive_access_bubble.h here, so there's a circular
include, and b) making the constant a public or friend member since we need it
here in the manager (the other constants are all protected). I'm going to leave
it here for now, pending OWNERs comments or a larger refactor later down the
line.

[msw, 2016/03/23 07:20:54]

nit: add a todo if you think it should be moved

+
+}
+
 ExclusiveAccessManager::ExclusiveAccessManager(
     ExclusiveAccessContext* exclusive_access_context)
     : exclusive_access_context_(exclusive_access_context),
       fullscreen_controller_(this),
-      mouse_lock_controller_(this) {
+      mouse_lock_controller_(this),
+      hold_timer_(true, false) {
 }
 
 ExclusiveAccessManager::~ExclusiveAccessManager() {
@@ -58,6 +66,9 @@ ExclusiveAccessManager::GetExclusiveAccessExitBubbleType() const {
   if (fullscreen_controller_.IsUserAcceptedFullscreen()) {
     if (fullscreen_controller_.IsPrivilegedFullscreenForTab())
       return EXCLUSIVE_ACCESS_BUBBLE_TYPE_NONE;
+    if (IsExperimentalFullscreenUIEnabled())
+      return
+        EXCLUSIVE_ACCESS_BUBBLE_TYPE_EXPERIMENTAL_FULLSCREEN_EXIT_INSTRUCTION;
     if (mouse_lock_controller_.IsMouseLocked())
       return EXCLUSIVE_ACCESS_BUBBLE_TYPE_FULLSCREEN_MOUSELOCK_EXIT_INSTRUCTION;
     if (mouse_lock_controller_.IsMouseLockRequested())
@@ -91,6 +102,11 @@ GURL ExclusiveAccessManager::GetExclusiveAccessBubbleURL() const {
 }
 
 // static
+bool ExclusiveAccessManager::IsExperimentalFullscreenUIEnabled() {
+  return base::FeatureList::IsEnabled(features::kExperimentalFullscreenUI);
+}
+
+// static
 bool ExclusiveAccessManager::IsSimplifiedFullscreenUIEnabled() {
   return base::FeatureList::IsEnabled(features::kSimplifiedFullscreenUI);
 }
@@ -112,15 +128,39 @@ void ExclusiveAccessManager::OnTabClosing(WebContents* web_contents) {
 
 bool ExclusiveAccessManager::HandleUserKeyPress(
     const content::NativeWebKeyboardEvent& event) {
-  if (event.windowsKeyCode != ui::VKEY_ESCAPE) {
-    OnUserInput();
+  if (IsExperimentalFullscreenUIEnabled()) {
+    if (event.windowsKeyCode != ui::VKEY_ESCAPE) {

[Matt Giuca, 2016/03/21 00:36:07]

This block got duplicated. It's the same for both the flag on and off, so move
it out (and keep the "return false").

[dominickn, 2016/03/21 21:58:04]

Good point, thanks

+      OnUserInput();
+    } else if (event.type == content::NativeWebKeyboardEvent::KeyUp &&
+              hold_timer_.IsRunning()) {
+      // Seeing a key up event on Esc with the hold timer running cancels the
+      // timer and doesn't exit. This means the user pressed Esc, but not long
+      // enough to trigger an exit
+      hold_timer_.Stop();
+    } else if (event.type == content::NativeWebKeyboardEvent::RawKeyDown &&
+              !hold_timer_.IsRunning()) {
+      // Seeing a key down event on Esc when the hold timer is stopped starts
+      // the timer. When the timer reaches 0, the callback will trigger an exit
+      // from fullscreen/mouselock.
+      hold_timer_.Start(
+          FROM_HERE,
+          base::TimeDelta::FromSeconds(kDurationToHoldEscapeToExitFullscreen),

[Matt Giuca, 2016/03/21 00:36:07]

FromSeconds takes an int, so this will round down to 1s. You want FromSecondsD.
(But also, the constant should be in ms, so then you want FromSeconds.)

[dominickn, 2016/03/21 21:58:04]

FromMillseeconds, done

+          base::Bind(&ExclusiveAccessManager::HandleUserHeldEscape,
+                     base::Unretained(this)));
+    }
+    // We never handle the keyboard event.
     return false;
+  } else {
+    if (event.windowsKeyCode != ui::VKEY_ESCAPE) {
+      OnUserInput();
+      return false;
+    }
+
+    bool handled = false;
+    handled = fullscreen_controller_.HandleUserPressedEscape();
+    handled |= mouse_lock_controller_.HandleUserPressedEscape();
+    return handled;
   }
-
-  bool handled = false;
-  handled = fullscreen_controller_.HandleUserPressedEscape();
-  handled |= mouse_lock_controller_.HandleUserPressedEscape();
-  return handled;
 }
 
 void ExclusiveAccessManager::OnUserInput() {
@@ -159,6 +199,7 @@ void ExclusiveAccessManager::RecordBubbleReshownUMA(
       break;
     case EXCLUSIVE_ACCESS_BUBBLE_TYPE_FULLSCREEN_BUTTONS:
     case EXCLUSIVE_ACCESS_BUBBLE_TYPE_FULLSCREEN_EXIT_INSTRUCTION:
+    case EXCLUSIVE_ACCESS_BUBBLE_TYPE_EXPERIMENTAL_FULLSCREEN_EXIT_INSTRUCTION:
     case EXCLUSIVE_ACCESS_BUBBLE_TYPE_BROWSER_FULLSCREEN_EXIT_INSTRUCTION:
     case EXCLUSIVE_ACCESS_BUBBLE_TYPE_EXTENSION_FULLSCREEN_EXIT_INSTRUCTION:
       // Only fullscreen in effect.
@@ -181,3 +222,8 @@ void ExclusiveAccessManager::RecordBubbleReshownUMA(
   if (mouselock)
     mouse_lock_controller_.RecordBubbleReshownUMA();
 }
+
+void ExclusiveAccessManager::HandleUserHeldEscape() {
+  fullscreen_controller_.HandleUserPressedEscape();
+  mouse_lock_controller_.HandleUserPressedEscape();
+}