Refcount touch tracking ids to prevent freeing them too early.

ui/events/x/events_x_unittest.cc

Index: ui/events/x/events_x_unittest.cc
diff --git a/ui/events/x/events_x_unittest.cc b/ui/events/x/events_x_unittest.cc
index 7517e408e17206e59b444b4fa7b2bfea6ca77f40..4032015a3d1b4a56fae4af1dbb71ebe8cbacd33d 100644
--- a/ui/events/x/events_x_unittest.cc
+++ b/ui/events/x/events_x_unittest.cc
@@ -289,6 +289,66 @@ TEST_F(EventsXTest, TouchEventBasic) {
   EXPECT_FLOAT_EQ(GetTouchAngle(scoped_xevent), 0.45f);
   EXPECT_FLOAT_EQ(GetTouchForce(scoped_xevent), 0.5f);
 }
+
+int GetTouchIdForTrackingId(uint32 tracking_id) {
+  int slot = 0;
+  bool success =
+      TouchFactory::GetInstance()->QuerySlotForTrackingID(tracking_id, &slot);
+  if (success)
+    return slot;
+  return -1;
+}
+
+TEST_F(EventsXTest, TouchEventIdRefcounting) {
+  std::vector<unsigned int> devices;
+  devices.push_back(0);
+  ui::SetUpTouchDevicesForTest(devices);
+  std::vector<Valuator> valuators;
+
+  ui::ScopedXI2Event scoped_xevent0;
+  ui::ScopedXI2Event scoped_xevent1;
+  ui::ScopedXI2Event scoped_xevent2;
+
+  const int kTrackingId0 = 5;
+  const int kTrackingId1 = 7;
+
+  // Increment ref count once for first touch.
+  scoped_xevent0.InitTouchEvent(
+      0, XI_TouchBegin, kTrackingId0, gfx::Point(10, 10), valuators);
+  GetTouchId(scoped_xevent0);
+  IncrementTouchIdRefCount(scoped_xevent0);

[sadrul, 2014/07/22 21:23:20]

Instead of calling GetTouchId()/IncrementTouchIdRefCount(), can you create a
ui::TouchEvent here (and below in lines 327:329, 337)? So something like:

   XI2Event xpress0;
   scoped_ptr<ui::TouchEvent> upress0(xpress0);
   XI2Event xpress1;
   for (i = 0 : 4) {
     scoped_ptr<ui::TouchEvent> upress1(xpress1);
     ...
    }

and so on
   

[tdresser, 2014/07/23 15:15:50]

Done.

+  EXPECT_EQ(0, GetTouchIdForTrackingId(kTrackingId0));
+
+  // Increment ref count 4 times for second touch.
+  scoped_xevent1.InitTouchEvent(
+      0, XI_TouchBegin, kTrackingId1, gfx::Point(10, 10), valuators);
+
+  for (int i = 0; i < 4; ++i) {
+    GetTouchId(scoped_xevent1);
+    IncrementTouchIdRefCount(scoped_xevent1);
+    EXPECT_EQ(1, GetTouchIdForTrackingId(kTrackingId1));
+  }
+
+  // Decrement ref count 3 times for second touch.
+  scoped_xevent1.InitTouchEvent(
+      0, XI_TouchEnd, kTrackingId1, gfx::Point(10, 10), valuators);
+
+  for (int i = 0; i < 3; ++i) {
+    ClearTouchIdIfReleased(scoped_xevent1);
+    EXPECT_EQ(1, GetTouchIdForTrackingId(kTrackingId1));
+  }
+
+  // This should clear the touch id of the second touch.
+  ClearTouchIdIfReleased(scoped_xevent1);
+  EXPECT_EQ(-1, GetTouchIdForTrackingId(kTrackingId1));
+
+  // This should clear the touch id of the first touch.
+  scoped_xevent0.InitTouchEvent(
+      0, XI_TouchEnd, kTrackingId0, gfx::Point(10, 10), valuators);
+
+  ClearTouchIdIfReleased(scoped_xevent0);
+  EXPECT_EQ(-1, GetTouchIdForTrackingId(kTrackingId0));
+}
 #endif
 
 TEST_F(EventsXTest, NumpadKeyEvents) {