EventSender::GestureFlingStart takes a source_device.

content/shell/renderer/test_runner/event_sender.cc

Index: content/shell/renderer/test_runner/event_sender.cc
diff --git a/content/shell/renderer/test_runner/event_sender.cc b/content/shell/renderer/test_runner/event_sender.cc
index e02fe0cef1c2ca25679949bc5cd748cdb726e9ee..de90e38342f6588b0a8ce48566c7e436a6296bf4 100644
--- a/content/shell/renderer/test_runner/event_sender.cc
+++ b/content/shell/renderer/test_runner/event_sender.cc
@@ -345,6 +345,9 @@ bool IsSystemKeyEvent(const WebKeyboardEvent& event) {
 #endif
 }
 
+const char* kSourceDeviceStringTouchpad = "touchpad";
+const char* kSourceDeviceStringTouchscreen = "touchscreen";
+
 }  // namespace
 
 class EventSenderBindings : public gin::Wrappable<EventSenderBindings> {
@@ -382,7 +385,11 @@ class EventSenderBindings : public gin::Wrappable<EventSenderBindings> {
   void SetTouchCancelable(bool cancelable);
   void DumpFilenameBeingDragged();
   void GestureFlingCancel();
-  void GestureFlingStart(float x, float y, float velocity_x, float velocity_y);
+  void GestureFlingStart(float x,
+                         float y,
+                         float velocity_x,
+                         float velocity_y,
+                         gin::Arguments* args);
   void GestureScrollFirstPoint(int x, int y);
   void TouchStart();
   void TouchMove();
@@ -717,12 +724,23 @@ void EventSenderBindings::GestureFlingCancel() {
     sender_->GestureFlingCancel();
 }
 
+// TODO(tdresser): Once we've migrated all calls to GestureFlingStart
+// to pass the device_string, change |args| to |std::string
+// device_string|. See crbug.com/456136 for details.
 void EventSenderBindings::GestureFlingStart(float x,
                                             float y,
                                             float velocity_x,
-                                            float velocity_y) {
+                                            float velocity_y,
+                                            gin::Arguments* args) {
+  std::string device_string = kSourceDeviceStringTouchpad;
+  if (!args->PeekNext().IsEmpty() && args->PeekNext()->IsString()) {
+    if (!args->GetNext(&device_string)) {
+      args->ThrowError();
+      return;
+    }
+  }
   if (sender_)
-    sender_->GestureFlingStart(x, y, velocity_x, velocity_y);
+    sender_->GestureFlingStart(x, y, velocity_x, velocity_y, device_string);
 }
 
 void EventSenderBindings::GestureScrollFirstPoint(int x, int y) {
@@ -1607,12 +1625,17 @@ void EventSender::GestureFlingCancel() {
 }
 
 void EventSender::GestureFlingStart(float x,
-                                     float y,
-                                     float velocity_x,
-                                     float velocity_y) {
+                                    float y,
+                                    float velocity_x,
+                                    float velocity_y,
+                                    std::string device_string) {
   WebGestureEvent event;
   event.type = WebInputEvent::GestureFlingStart;
 
+  event.sourceDevice = blink::WebGestureDeviceTouchscreen;

[Rick Byers, 2015/02/07 11:20:23]

This should probably have logic similar to GestureEvent below where unrecognized
strings throw an error, right?

[tdresser, 2015/02/09 14:48:08]

My plan was to switch to use |std::string| instead of |gin::Arguments| once I've
updated blink to always pass a device_string. Without a |gin::Arguments|, you
can't throw an error.

This approach has precedent, for example, EventSender::MouseDown defaults to
assuming a middle click.
https://code.google.com/p/chromium/codesearch#chromium/src/content/shell/rend...

If you'd prefer, I can switch to always passing a |gin::Arguments|.

+  if (device_string == kSourceDeviceStringTouchpad)
+    event.sourceDevice = blink::WebGestureDeviceTouchpad;
+
   event.x = x;
   event.y = y;
   event.globalX = event.x;
@@ -1998,9 +2021,9 @@ void EventSender::GestureEvent(WebInputEvent::Type type,
       args->ThrowError();
       return;
     }
-    if (device_string == "touchpad") {
+    if (device_string == kSourceDeviceStringTouchpad) {
       event.sourceDevice = blink::WebGestureDeviceTouchpad;
-    } else if (device_string == "touchscreen") {
+    } else if (device_string == kSourceDeviceStringTouchscreen) {
       event.sourceDevice = blink::WebGestureDeviceTouchscreen;
     } else {
       args->ThrowError();