Add the pointer type of pen to the synthetic WebMousEvent

content/browser/renderer_host/input/synthetic_pointer_driver.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/input/synthetic_pointer_driver.h"
 
 #include "base/memory/ptr_util.h"
 #include "content/browser/renderer_host/input/synthetic_mouse_driver.h"
 #include "content/browser/renderer_host/input/synthetic_touch_driver.h"
 
 namespace content {
 
 SyntheticPointerDriver::SyntheticPointerDriver() {}
 SyntheticPointerDriver::~SyntheticPointerDriver() {}
 
 // static
 std::unique_ptr<SyntheticPointerDriver> SyntheticPointerDriver::Create(
     SyntheticGestureParams::GestureSourceType gesture_source_type) {
-  if (gesture_source_type == SyntheticGestureParams::TOUCH_INPUT) {
-    return base::MakeUnique<SyntheticTouchDriver>();
-  } else if (gesture_source_type == SyntheticGestureParams::MOUSE_INPUT) {
-    return base::MakeUnique<SyntheticMouseDriver>();
-  } else {
-    NOTREACHED() << "Invalid gesture source type";
-    return std::unique_ptr<SyntheticPointerDriver>();
+  switch (gesture_source_type) {
+    case SyntheticGestureParams::TOUCH_INPUT:
+      return base::MakeUnique<SyntheticTouchDriver>();
+    case SyntheticGestureParams::MOUSE_INPUT:
+    case SyntheticGestureParams::PEN_INPUT:

[Navid Zolghadr, 2017/01/19 15:46:22]

Do you think it is worth to introduce the eraser input at the same time? I
believe the idea there was to you use the end of the pen to erase something. So
some pens will report a new type if I recall correctly from what Mustaq was
saying and for some others instead of the end of the pen you need to press the
eraser button. I wonder if we need to support both cases. Basically letting the
user to either set the pointer type to eraser or just set the eraser button
(which I believe we should have already if we just add them to our switch
cases). WDYT?

[lanwei, 2017/01/20 14:42:21]

As we discussed offline, we decide to add just pen type right now, thanks!

+      return base::MakeUnique<SyntheticMouseDriver>(gesture_source_type);
+    case SyntheticGestureParams::DEFAULT_INPUT:
+      return std::unique_ptr<SyntheticPointerDriver>();
   }
+  NOTREACHED();
+  return std::unique_ptr<SyntheticPointerDriver>();
 }
 
 // static
 double SyntheticPointerDriver::ConvertTimestampToSeconds(
     const base::TimeTicks& timestamp) {
   return (timestamp - base::TimeTicks()).InSecondsF();
 }
 
 }  // namespace content