Prevent race condition when cancelling long-press for scroll.

When dragging between workspaces in rapid succession, the canceling of the
original long-press timer wasn't being triggered correctly.  (When the timer
fires, it might read an invalid Workspace.allowLongPress() value.)

This patchset correctly cancels any pending long-press timers once a desktop
scroll begins, and we don't need to rely on the allowLongPress() value.
diff --git a/src/com/android/launcher/LauncherAppWidgetHostView.java b/src/com/android/launcher/LauncherAppWidgetHostView.java
index 1e21a19..da5b3a0 100644
--- a/src/com/android/launcher/LauncherAppWidgetHostView.java
+++ b/src/com/android/launcher/LauncherAppWidgetHostView.java
@@ -98,4 +98,14 @@
         mPendingCheckForLongPress.rememberWindowAttachCount();
         postDelayed(mPendingCheckForLongPress, ViewConfiguration.getLongPressTimeout());
     }
+
+    @Override
+    public void cancelLongPress() {
+        super.cancelLongPress();
+
+        mHasPerformedLongPress = false;
+        if (mPendingCheckForLongPress != null) {
+            removeCallbacks(mPendingCheckForLongPress);
+        }
+    }
 }