[Mac] Factor out keyboard shortcut handling from ChromeEventProcessingWindow.

chrome/browser/ui/cocoa/chrome_command_dispatcher_delegate.mm

+// Copyright 2015 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.
+
+#import "chrome/browser/ui/cocoa/chrome_command_dispatcher_delegate.h"
+
+#include "base/logging.h"
+#include "chrome/browser/global_keyboard_shortcuts_mac.h"
+#include "chrome/browser/ui/browser_commands.h"
+#include "chrome/browser/ui/browser_finder.h"
+#import "chrome/browser/ui/cocoa/browser_window_controller_private.h"
+#import "chrome/browser/ui/cocoa/tabs/tab_strip_controller.h"
+
+namespace {
+
+// Type of functions listed in global_keyboard_shortcuts_mac.h.
+typedef int (*KeyToCommandMapper)(bool, bool, bool, bool, int, unichar);
+
+// If the event is for a Browser window, and the key combination has an
+// associated command, execute the command.
+bool HandleExtraKeyboardShortcut(
+    NSEvent* event,
+    NSWindow* window,
+    KeyToCommandMapper command_for_keyboard_shortcut) {
+  // Extract info from |event|.
+  NSUInteger modifers = [event modifierFlags];
+  const bool command = modifers & NSCommandKeyMask;
+  const bool shift = modifers & NSShiftKeyMask;
+  const bool control = modifers & NSControlKeyMask;
+  const bool option = modifers & NSAlternateKeyMask;
+  const int key_code = [event keyCode];
+  const unichar key_char = KeyCharacterForEvent(event);
+
+  int cmd = command_for_keyboard_shortcut(command, shift, control, option,
+                                          key_code, key_char);
+
+  if (cmd == -1)
+    return false;
+
+  // Only handle event if this is a browser window.
+  Browser* browser = chrome::FindBrowserWithWindow(window);
+  if (!browser)
+    return false;
+
+  chrome::ExecuteCommand(browser, cmd);
+  return true;
+}
+
+bool HandleExtraWindowKeyboardShortcut(NSEvent* event, NSWindow* window) {
+  return HandleExtraKeyboardShortcut(event, window,
+                                     CommandForWindowKeyboardShortcut);
+}
+
+bool HandleDelayedWindowKeyboardShortcut(NSEvent* event, NSWindow* window) {
+  return HandleExtraKeyboardShortcut(event, window,
+                                     CommandForDelayedWindowKeyboardShortcut);
+}
+
+bool HandleExtraBrowserKeyboardShortcut(NSEvent* event, NSWindow* window) {
+  return HandleExtraKeyboardShortcut(event, window,
+                                     CommandForBrowserKeyboardShortcut);
+}
+
+}  // namespace
+
+@implementation ChromeCommandDispatcherDelegate
+
+- (BOOL)handleExtraKeyboardShortcut:(NSEvent*)event window:(NSWindow*)window {
+  return HandleExtraBrowserKeyboardShortcut(event, window) ||
+         HandleExtraWindowKeyboardShortcut(event, window) ||
+         HandleDelayedWindowKeyboardShortcut(event, window);
+}
+
+- (BOOL)handledByExtensionCommand:(NSEvent*)event
+                     isRedispatch:(BOOL)isRedispatch {
+  // Some extension commands have higher priority than web content, and some
+  // have lower priority. Regardless of whether the event is being redispatched,
+  // let the extension system try to handle the event. In case this is a
+  // redispatched event, |event.window| gives the correct window.

[tapted, 2015/08/18 07:22:12]

What about if it isn't redispatched? (is event.window always correct?) This
might be irrelevant if we can move this back to CEPW

[jackhou1, 2015/08/25 06:31:12]

I think it should be fine, pretty sure the logic is the same as it was in CEPW
(I just added some commentary).

+  if (event.window) {
+    BrowserWindowController* controller = [event.window windowController];
+    if ([controller respondsToSelector:@selector(handledByExtensionCommand:
+                                                                  priority:)]) {
+      ui::AcceleratorManager::HandlerPriority priority =
+          isRedispatch ? ui::AcceleratorManager::kNormalPriority
+                       : ui::AcceleratorManager::kHighPriority;
+      if ([controller handledByExtensionCommand:event priority:priority])
+        return YES;
+    }
+  }
+  return NO;
+}
+
+- (BOOL)prePerformKeyEquivalent:(NSEvent*)event window:(NSWindow*)window {
+  // Handle per-window shortcuts like cmd-1, but do not handle browser-level
+  // shortcuts like cmd-left (else, cmd-left would do history navigation even
+  // if e.g. the Omnibox has focus).
+  return HandleExtraWindowKeyboardShortcut(event, window);
+}
+
+- (BOOL)postPerformKeyEquivalent:(NSEvent*)event window:(NSWindow*)window {
+  // Handle per-window shortcuts like Esc after giving everybody else a chance
+  // to handle them
+  return HandleDelayedWindowKeyboardShortcut(event, window);
+}
+
+@end  // ChromeCommandDispatchDelegate