ppapi: Opt-in to receive synthetic mouse events for touch-events.

If a pepper plugin did not opt-in to receive touch-events, then opt-in to receive
synthetic mouse-events instead.

BUG=138362

Review URL: https://codereview.chromium.org/11418134

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170097 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 9 insertions, 1 deletions

diff --git a/ppapi/api/ppb_input_event.idl b/ppapi/api/ppb_input_event.idl
index 73e279d..496a0a6 100644
--- a/ppapi/api/ppb_input_event.idl
+++ b/ppapi/api/ppb_input_event.idl
@@ -265,7 +265,12 @@ enum PP_InputEvent_Class {
    *
    * Request touch events only if you intend to handle them. If the browser
    * knows you do not need to handle touch events, it can handle them at a
-   * higher level and achieve higher performance.
+   * higher level and achieve higher performance. If the plugin does not
+   * register for touch-events, then it will receive synthetic mouse events that
+   * are generated from the touch events (e.g. mouse-down for touch-start,
+   * mouse-move for touch-move (with left-button down), and mouse-up for
+   * touch-end. If the plugin does register for touch events, then the synthetic
+   * mouse events are not created.
    */
   PP_INPUTEVENT_CLASS_TOUCH = 1 << 3,
 
@@ -306,6 +311,9 @@ interface PPB_InputEvent {
    * processed very quickly, may have a noticeable effect on the performance of
    * the page.
    *
+   * Note that synthetic mouse events will be generated from touch events if
+   * (and only if) the you do not request touch events.
+   *
    * When requesting input events through this function, the events will be
    * delivered and <i>not</i> bubbled to the page. This means that even if you
    * aren't interested in the message, no other parts of the page will get