Android mouse events shouldn't appear as TouchEvents

content/browser/android/content_view_core_impl.cc

Index: content/browser/android/content_view_core_impl.cc
diff --git a/content/browser/android/content_view_core_impl.cc b/content/browser/android/content_view_core_impl.cc
index a7f92639fa22c313db88252bc64615f8ebf06c4a..745f2a203b5ade878a8274e09c991c6e3a4ecb2c 100644
--- a/content/browser/android/content_view_core_impl.cc
+++ b/content/browser/android/content_view_core_impl.cc
@@ -61,6 +61,7 @@
 #include "ui/events/blink/blink_event_util.h"
 #include "ui/events/blink/web_input_event_traits.h"
 #include "ui/events/event_utils.h"
+#include "ui/events/gesture_detection/motion_event.h"
 #include "ui/gfx/android/java_bitmap.h"
 #include "ui/gfx/geometry/point_conversions.h"
 #include "ui/gfx/geometry/size_conversions.h"
@@ -217,7 +218,8 @@ ContentViewCoreImpl::ContentViewCoreImpl(
       page_scale_(1),
       dpi_scale_(ui::GetScaleFactorForNativeView(&view_)),
       device_orientation_(0),
-      accessibility_enabled_(false) {
+      accessibility_enabled_(false),
+      button_state_(0) {
   CHECK(web_contents) <<
       "A ContentViewCoreImpl should be created with a valid WebContents.";
   DCHECK(window_android);
@@ -973,24 +975,74 @@ jboolean ContentViewCoreImpl::OnTouchEvent(
                                : rwhv->OnTouchEvent(event);
 }
 
-jboolean ContentViewCoreImpl::SendMouseMoveEvent(
+jboolean ContentViewCoreImpl::SendMouseEvent(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj,

[dtapuska, 2016/09/20 20:56:16]

Can we pass const JavaParamRef<jobject>& motion_event, in here to make it look
similar to touch?

and maybe the meta state?

[mustaq, 2016/09/21 19:31:29]

- Done adding meta state.

- Skipped passing motion_event ref because touch is the only exception here that
it may pack multiple pointers. Like most other cases here (SendMouseWheelEvent,
ScrollBegin, SingleTap), unpacked cases don't need the Java ref.
MotionEventAndroid already allows that through DCHECKs.

     jlong time_ms,
+    jint android_action,
     jfloat x,
     jfloat y,
-    jint tool_type) {
+    jint pointer_id,
+    jfloat pressure,
+    jfloat orientation,
+    jfloat tilt,
+    jint android_button_state,
+    jint android_tool_type) {
+
   RenderWidgetHostViewAndroid* rwhv = GetRenderWidgetHostViewAndroid();
   if (!rwhv)
     return false;
 
-  blink::WebMouseEvent event = WebMouseEventBuilder::Build(
-      WebInputEvent::MouseMove,
-      blink::WebMouseEvent::Button::NoButton,
-      time_ms / 1000.0, x / dpi_scale(), y / dpi_scale(), 0, 1,
-      ui::ToWebPointerType(static_cast<ui::MotionEvent::ToolType>(tool_type)));
-
-  rwhv->SendMouseEvent(event);
+  // Construct a motion_event object minimally, only to convert the raw
+  // parameters to ui::MotionEvent values. Since we used only the cached values
+  // at index=0, it is okay to even pass a null event to the constructor.
+  ui::MotionEventAndroid::Pointer pointer0(
+      pointer_id, x, y, 0.0f /* touch_major */, 0.0f /* touch_minor */,
+      orientation, tilt, android_tool_type);
+
+  ui::MotionEventAndroid motion_event(1.f / dpi_scale(),
+      env,
+      0 /* event */,
+      time_ms,
+      android_action,
+      1 /* pointer_count */,
+      0 /* history_size */,
+      0 /* action_index */,
+      android_button_state,
+      0 /* meta_state */,
+      0 /* raw_offset_x_pixels */,
+      0 /* raw_offset_y_pixels */,
+      pointer0,
+      pointer0 /* pointer1 */);
+
+  blink::WebInputEvent::Type webMouseEventType =
+      ui::ToWebMouseEventType(motion_event.GetAction());
+
+  int old_button_state = button_state_;
+
+  // Ignore button state in MouseMove events: we have seen cases that a
+  // MouseMove with updated button state often precedes a MouseDown/MouseUp.
+  if (webMouseEventType != blink::WebInputEvent::MouseMove)
+    button_state_ = motion_event.GetButtonState();
+
+  blink::WebMouseEvent mouse_event = WebMouseEventBuilder::Build(
+      webMouseEventType,
+      time_ms / 1000.0,
+      motion_event.GetX(0),
+      motion_event.GetY(0),
+      button_state_ /* modifiers */,
+      button_state_ ? 1 : 0 /* click count */,
+      motion_event.GetPointerId(0),
+      motion_event.GetPressure(0),
+      motion_event.GetOrientation(0),
+      motion_event.GetTilt(0),
+      old_button_state,
+      button_state_,
+      motion_event.GetToolType(0));
+  // TODO(mustaq): mouse_event.modifiers should include fields from
+  // MotionEvent.getMetaState().
+
+  rwhv->SendMouseEvent(mouse_event);
   return true;
 }