ash: Fix a screen-locking crash.

ash/wm/lock_state_controller.cc

Index: ash/wm/lock_state_controller.cc
diff --git a/ash/wm/lock_state_controller.cc b/ash/wm/lock_state_controller.cc
index 09a46afa2a1436404485a642a920205f69a4cad8..754d4b68eacd050d43832215092f849f1288359c 100644
--- a/ash/wm/lock_state_controller.cc
+++ b/ash/wm/lock_state_controller.cc
@@ -16,6 +16,7 @@
 #include "ash/wm/session_state_animator.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
+#include "base/strings/string_util.h"
 #include "base/timer/timer.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/compositor/layer_animation_sequence.h"
@@ -584,9 +585,12 @@ void LockStateController::LockAnimationCancelled() {
 }
 
 void LockStateController::PreLockAnimationFinished(bool request_lock) {
-  can_cancel_lock_animation_ = false;
   VLOG(1) << "PreLockAnimationFinished";
+  can_cancel_lock_animation_ = false;
+
   if (request_lock) {
+    DCHECK(!system_is_locked_) << "Got request to lock already-locked system "
+                               << "at completion of pre-lock animation";
     Shell::GetInstance()->metrics()->RecordUserMetricsAction(
         shutdown_after_lock_ ?
         UMA_ACCEL_LOCK_SCREEN_POWER_BUTTON :
@@ -594,24 +598,23 @@ void LockStateController::PreLockAnimationFinished(bool request_lock) {
     delegate_->RequestLockScreen();
   }
 
-  int lock_timeout = kLockFailTimeoutMs;
-
+  // Don't start the lock-fail timer if the screen was already locked while the
+  // animation was going.
+  if (!system_is_locked_) {

[stevenjb, 2014/08/01 23:23:56]

nit: Early exit

[Daniel Erat, 2014/08/01 23:52:06]

Done.

+    base::TimeDelta timeout =
+        base::TimeDelta::FromMilliseconds(kLockFailTimeoutMs);
 #if defined(OS_CHROMEOS)
-  std::string board = base::SysInfo::GetLsbReleaseBoard();
-
-  // Increase lock timeout for slower hardware, see http://crbug.com/350628
-  if (board == "x86-mario" ||
-      board.substr(0, 8) == "x86-alex" ||
-      board.substr(0, 7) == "x86-zgb") {
-    lock_timeout *= 2;
-  }
+    // Increase lock timeout for slower hardware, see http://crbug.com/350628
+    const std::string board = base::SysInfo::GetLsbReleaseBoard();
+    if (board == "x86-mario" ||
+        StartsWithASCII(board, "x86-alex", true) ||
+        StartsWithASCII(board, "x86-zgb", true)) {

[stevenjb, 2014/08/01 23:23:56]

nit: what is "true"?

[Daniel Erat, 2014/08/01 23:52:06]

done (but just because it still fits without wrapping :-P)

+      timeout *= 2;
+    }
 #endif
-
-  lock_fail_timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromMilliseconds(lock_timeout),
-      this,
-      &LockStateController::OnLockFailTimeout);
+    lock_fail_timer_.Start(
+        FROM_HERE, timeout, this, &LockStateController::OnLockFailTimeout);
+  }
 }
 
 void LockStateController::PostLockAnimationFinished() {