Do not show notifications when in fullscreen or screensaver mode....

chrome/browser/idle_mac.mm

 // Copyright (c) 2009 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 "chrome/browser/idle.h"
+#import "chrome/browser/idle.h"
 
-#include <CoreGraphics/CGEventSource.h>
+#import <Cocoa/Cocoa.h>
+#import <CoreGraphics/CGEventSource.h>
+
+@interface MacScreenMonitor : NSObject {
+ @private
+  BOOL screensaverRunning_;
+  BOOL screenLocked_;
+}
+
+- (BOOL)isScreensaverRunning;
+- (BOOL)isScreenLocked;
+
+@end
+
+@implementation MacScreenMonitor
+
+- (id)init {
+  if ((self = [super init])) {
+    NSDistributedNotificationCenter* distCenter =
+          [NSDistributedNotificationCenter defaultCenter];
+    [distCenter addObserver:self
+                   selector:@selector(onScreenSaverStarted:)
+                       name:@"com.apple.screensaver.didstart"
+                     object:nil];
+    [distCenter addObserver:self
+                   selector:@selector(onScreenSaverStopped:)
+                       name:@"com.apple.screensaver.didstop"
+                     object:nil];
+    [distCenter addObserver:self
+                   selector:@selector(onScreenLocked:)
+                       name:@"com.apple.screenIsLocked"
+                     object:nil];
+    [distCenter addObserver:self
+                   selector:@selector(onScreenUnlocked:)
+                       name:@"com.apple.screenIsUnlocked"
+                     object:nil];
+  }
+  return self;
+}
+
+- (void)dealloc {
+  [[NSDistributedNotificationCenter defaultCenter] removeObject:self];
+  [super dealloc];
+}
+
+- (void)onScreenSaverStarted:(NSNotification*)notification {
+   screensaverRunning_ = YES;
+}
+
+- (void)onScreenSaverStopped:(NSNotification*)notification {
+   screensaverRunning_ = NO;
+}
+
+- (void)onScreenLocked:(NSNotification*)notification {
+   screenLocked_ = YES;
+}
+
+- (void)onScreenUnlocked:(NSNotification*)notification {
+   screenLocked_ = NO;
+}
+
+- (BOOL)isScreensaverRunning {
+  return screensaverRunning_;
+}
+
+- (BOOL)isScreenLocked {
+  return screenLocked_;
+}
+
+@end
+
+MacScreenMonitor* g_screenMonitor = nil;
+
+void InitIdleMonitor() {
+  if (!g_screenMonitor)
+    g_screenMonitor = [[MacScreenMonitor alloc] init];
+}
+
+void StopIdleMonitor() {
+  [g_screenMonitor release];
+  g_screenMonitor = nil;
+}
 
 IdleState CalculateIdleState(unsigned int idle_threshold) {
+  if ([g_screenMonitor isScreensaverRunning] ||
+      [g_screenMonitor isScreenLocked])
+    return IDLE_STATE_LOCKED;
+
   unsigned int idle_time = CGEventSourceSecondsSinceLastEventType(
      kCGEventSourceStateCombinedSessionState,
      kCGAnyInputEventType);
   if (idle_time >= idle_threshold)
     return IDLE_STATE_IDLE;
+
   return IDLE_STATE_ACTIVE;
 }