Remove references to WebTouchEvent.targetTouches

content/renderer/browser_plugin/browser_plugin.cc

Index: content/renderer/browser_plugin/browser_plugin.cc
diff --git a/content/renderer/browser_plugin/browser_plugin.cc b/content/renderer/browser_plugin/browser_plugin.cc
index d7ba64b88e5514c9cb2d25e06f651a7e6968d74a..71dc8c2d70b378d2fa6c4925e6085752fb3671de 100644
--- a/content/renderer/browser_plugin/browser_plugin.cc
+++ b/content/renderer/browser_plugin/browser_plugin.cc
@@ -582,42 +582,48 @@ bool BrowserPlugin::handleInputEvent(const blink::WebInputEvent& event,
   if (blink::WebInputEvent::isTouchEventType(event.type)) {
     const blink::WebTouchEvent* orig_touch_event =
         static_cast<const blink::WebTouchEvent*>(&event);
-
-    touch_event.reset(new blink::WebTouchEvent());
-    memcpy(touch_event.get(), orig_touch_event, sizeof(blink::WebTouchEvent));
-
-    // TODO(bokan): Blink passes back a WebGestureEvent with a touches,
-    // changedTouches, and targetTouches lists; however, it doesn't set
-    // the state field on the touches which is what the RenderWidget uses
-    // to create a WebCore::TouchEvent. crbug.com/358132 tracks removing
-    // these multiple lists from WebTouchEvent since they lead to misuse
-    // like this and are functionally unused. In the mean time we'll setup
-    // the state field here manually to fix multi-touch BrowserPlugins.
-    for (size_t i = 0; i < touch_event->touchesLength; ++i) {
-      blink::WebTouchPoint& touch = touch_event->touches[i];
-      touch.state = blink::WebTouchPoint::StateStationary;
-      for (size_t j = 0; j < touch_event->changedTouchesLength; ++j) {
-        blink::WebTouchPoint& changed_touch = touch_event->changedTouches[j];
-        if (touch.id == changed_touch.id) {
-          touch.state = changed_touch.state;
-          break;
+    // TODO(jdduke): Remove this branch when Blink starts forwarding
+    // WebTouchEvents with a fully populated |touches| field.
+    if (orig_touch_event->changedTouchesLength) {
+      touch_event.reset(new blink::WebTouchEvent());
+      memcpy(touch_event.get(), orig_touch_event, sizeof(blink::WebTouchEvent));
+
+      if (touch_event->changedTouchesLength)

[bokan, 2014/09/09 20:17:38]

Nit: I should have done this when i was here...can you add curly braces around
this 'if'

[jdduke (slow), 2014/09/09 20:52:24]

Done.

+        // TODO(bokan): Blink passes back a WebGestureEvent with touches and
+        // changedTouches lists; however, it doesn't set the state field on the
+        // touches which is what the RenderWidget uses to create a
+        // WebCore::TouchEvent. crbug.com/358132 tracks removing these multiple
+        // from WebTouchEvent since they lead to misuse like this and are
+        // functionally unused. In the mean time we'll setup the state field
+        // here manually to fix multi-touch BrowserPlugins.
+        for (size_t i = 0; i < touch_event->touchesLength; ++i) {
+          blink::WebTouchPoint& touch = touch_event->touches[i];
+          touch.state = blink::WebTouchPoint::StateStationary;
+          for (size_t j = 0; j < touch_event->changedTouchesLength; ++j) {
+            blink::WebTouchPoint& changed_touch =
+                touch_event->changedTouches[j];
+            if (touch.id == changed_touch.id) {
+              touch.state = changed_touch.state;
+              break;
+            }
+          }
         }
-      }
-    }
 
-    // For End and Cancel, Blink gives BrowserPlugin a list of touches that
-    // are down, but the browser process expects a list of all touches. We
-    // modify these events here to match these expectations.
-    if (event.type == blink::WebInputEvent::TouchEnd ||
-        event.type == blink::WebInputEvent::TouchCancel) {
-      if (touch_event->changedTouchesLength > 0) {
-        memcpy(&touch_event->touches[touch_event->touchesLength],
-               &touch_event->changedTouches,
+      // For End and Cancel, Blink gives BrowserPlugin a list of touches that
+      // are down, but the browser process expects a list of all touches. We
+      // modify these events here to match these expectations.
+      if (event.type == blink::WebInputEvent::TouchEnd ||
+          event.type == blink::WebInputEvent::TouchCancel) {
+        if (touch_event->changedTouchesLength > 0) {
+          memcpy(
+              &touch_event->touches[touch_event->touchesLength],
+              &touch_event->changedTouches,
               touch_event->changedTouchesLength * sizeof(blink::WebTouchPoint));
-        touch_event->touchesLength += touch_event->changedTouchesLength;
+          touch_event->touchesLength += touch_event->changedTouchesLength;
+        }
       }
+      modified_event = touch_event.get();
     }
-    modified_event = touch_event.get();
   }
 
   if (blink::WebInputEvent::isKeyboardEventType(event.type) &&