Mac: Honour the user preference for triggering QuickLook with Force Click

ui/base/cocoa/appkit_utils.mm

Index: ui/base/cocoa/appkit_utils.mm
diff --git a/ui/base/cocoa/appkit_utils.mm b/ui/base/cocoa/appkit_utils.mm
index ce672699f5d16a602aa511987a549b75a9967ddd..1b0a61b2060314e77da4814f97610fc8f9590ded 100644
--- a/ui/base/cocoa/appkit_utils.mm
+++ b/ui/base/cocoa/appkit_utils.mm
@@ -9,12 +9,6 @@
 
 namespace {
 
-// Gets an NSImage given an image id.
-NSImage* GetImage(int image_id) {
-  return ui::ResourceBundle::GetSharedInstance().GetNativeImageNamed(image_id)
-      .ToNSImage();
-}
-
 // Double-click in window title bar actions.
 enum class DoubleClickAction {
   NONE,
@@ -22,6 +16,20 @@ enum class DoubleClickAction {
   MAXIMIZE,
 };
 
+// Values of com.apple.trackpad.forceClick corresponding to "Look up & data
+// detectors" in System Preferences -> Trackpad -> Point & Click.
+enum class ForceTouchAction {
+  NONE = 0,        // Unchecked or set to "Tap with three fingers".
+  QUICK_LOOK = 1,  // Set to "Force Click with one finger".
+};
+
+// Gets an NSImage given an image id.
+NSImage* GetImage(int image_id) {
+  return ui::ResourceBundle::GetSharedInstance()
+      .GetNativeImageNamed(image_id)
+      .ToNSImage();
+}
+
 // The action to take when the user double-clicks in the window title bar.
 DoubleClickAction WindowTitleBarDoubleClickAction() {
   // El Capitan introduced a Dock preference to configure the window title bar
@@ -95,4 +103,10 @@ void WindowTitlebarReceivedDoubleClick(NSWindow* window, id sender) {
   }
 }
 
+bool ForceClickInvokesQuickLook() {
+  return [[NSUserDefaults standardUserDefaults]
+             integerForKey:@"com.apple.trackpad.forceClick"] ==
+         static_cast<NSInteger>(ForceTouchAction::QUICK_LOOK);
+}
+
 }  // namespace ui