aura: Fix cursor visibility, and a crash on mouse-wheel.

Fix cursor visibility so that a cursor is hidden only if a touch device is
available.

BUG=cursor hides on desktop
TEST=none

Review URL: http://codereview.chromium.org/8319009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@105900 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 11 insertions, 3 deletions

diff --git a/ui/base/touch/touch_factory.cc b/ui/base/touch/touch_factory.cc
index fcab846..b3f9e51 100644
--- a/ui/base/touch/touch_factory.cc
+++ b/ui/base/touch/touch_factory.cc
@@ -135,6 +135,7 @@ TouchFactory::TouchFactory()
       keep_mouse_cursor_(false),
       cursor_timer_(),
       pointer_device_lookup_(),
+      touch_device_available_(false),
       touch_device_list_(),
 #if defined(USE_XI2_MT)
       min_available_slot_(0),
@@ -202,6 +203,7 @@ void TouchFactory::UpdateDeviceList(Display* display) {
   // If XInput2 is not supported, this will return null (with count of -1) so
   // we assume there cannot be any touch devices.
   int count = 0;
+  touch_device_available_ = false;
   touch_device_lookup_.reset();
   touch_device_list_.clear();
 #if !defined(USE_XI2_MT)
@@ -212,6 +214,7 @@ void TouchFactory::UpdateDeviceList(Display* display) {
       if (devtype && !strcmp(devtype, XI_TOUCHSCREEN)) {
         touch_device_lookup_[devlist[i].id] = true;
         touch_device_list_[devlist[i].id] = true;
+        touch_device_available_ = true;
       }
     }
   }
@@ -245,6 +248,7 @@ void TouchFactory::UpdateDeviceList(Display* display) {
         if (tci->mode == XIDirectTouch) {
           touch_device_lookup_[devinfo->deviceid] = true;
           touch_device_list_[devinfo->deviceid] = true;
+          touch_device_available_ = true;
         }
       }
     }
@@ -455,11 +459,12 @@ void TouchFactory::SetCursorVisible(bool show, bool start_timer) {
   Display* display = ui::GetXDisplay();
   Window window = DefaultRootWindow(display);
 
-  if (is_cursor_visible_) {
+  // Hide the cursor only if there's a chance that the user will be using touch
+  // (i.e. if a touch device is available).
+  if (is_cursor_visible_)
     XDefineCursor(display, window, arrow_cursor_);
-  } else {
+  else if (touch_device_available_)
     XDefineCursor(display, window, invisible_cursor_);
-  }
 }
 
 void TouchFactory::SetupValuator() {
diff --git a/ui/base/touch/touch_factory.h b/ui/base/touch/touch_factory.h
index 3b1b5f1..158d2e0 100644
--- a/ui/base/touch/touch_factory.h
+++ b/ui/base/touch/touch_factory.h
@@ -188,6 +188,9 @@ class UI_EXPORT TouchFactory {
   // A quick lookup table for determining if a device is a touch device.
   std::bitset<kMaxDeviceNum> touch_device_lookup_;
 
+  // Indicates whether a touch device is currently available or not.
+  bool touch_device_available_;
+
   // The list of touch devices. For testing/debugging purposes, a mouse-device
   // can sometimes be treated as a touch device. The key in the map represents
   // the device id, and the value represents if the device is a real touch