Remove selection as default action of mousemove

Selection and dragging should be done regardless of whether js calls preventDefault on mousemove or pointermove events according to the spec: https://w3c.github.io/uievents/#event-type-mousemove This cl makes Chrome to handle selection/dragging regardless of return value of js handler to match other browsers. Bug: 346473 Change-Id: I71f2c808f224be23ffbc80ee25e2897a9dc9f090 Reviewed-on: https://chromium-review.googlesource.com/1112628Reviewed-by: Lan Wei <lanwei@chromium.org> Reviewed-by: Ella Ge <eirage@chromium.org> Reviewed-by: Dave Tapuska <dtapuska@chromium.org> Commit-Queue: Navid Zolghadr <nzolghadr@chromium.org> Cr-Commit-Position: refs/heads/master@{#571553}

Remove selection as default action of mousemove
Selection and dragging should be done regardless of whether js calls preventDefault on mousemove or pointermove events according to the spec: https://w3c.github.io/uievents/#event-type-mousemove This cl makes Chrome to handle selection/dragging regardless of return value of js handler to match other browsers. Bug: 346473 Change-Id: I71f2c808f224be23ffbc80ee25e2897a9dc9f090 Reviewed-on: https://chromium-review.googlesource.com/1112628Reviewed-by: Lan Wei <lanwei@chromium.org> Reviewed-by: Ella Ge <eirage@chromium.org> Reviewed-by: Dave Tapuska <dtapuska@chromium.org> Commit-Queue: Navid Zolghadr <nzolghadr@chromium.org> Cr-Commit-Position: refs/heads/master@{#571553}
76a593e2 · Navid Zolghadr · Commit Bot · 5f2b1f71 · 76a593e2 · 76a593e2
Commit 76a593e2 authored Jun 29, 2018 by Navid Zolghadr Committed by Commit Bot Jun 29, 2018
2 changed files
--- a/third_party/WebKit/LayoutTests/fast/events/drag-on-mouse-move-cancelled.html
+++ b/third_party/WebKit/LayoutTests/fast/events/drag-on-mouse-move-cancelled.html
+<!DOCTYPE html>
+<script src='../../resources/testharness.js'></script>
+<script src='../../resources/testharnessreport.js'></script>
+<p id="text">
+TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT TEXT
+</p>
+<script>
+    var testElem = document.getElementById("text");
+    testElem.addEventListener("mousemove", function(event) {
+      event.preventDefault();
+    }, false);
+
+    var testCancelledMouseMoveSelect = async_test('Tests whether cancelled mousemove can start text selection.');
+
+    if (window.chrome && chrome.gpuBenchmarking) {
+      var rect = testElem.getBoundingClientRect();
+      var text_x = rect.left;
+      var text_y = rect.top + rect.height / 2;
+
+      var pointerActions =
+        [{source: "mouse",
+          actions: [
+            { name: "pointerDown", x: text_x + 10, y: text_y },
+            { name: "pointerMove", x: text_x + 50, y: text_y },
+            { name: "pointerMove", x: text_x + 150, y: text_y },
+            { name: "pointerMove", x: text_x + 200, y: text_y },
+            { name: "pointerUp" }]}];
+      chrome.gpuBenchmarking.pointerActionSequence(pointerActions, () => {
+        testCancelledMouseMoveSelect.step(function() {
+          assert_greater_than(window.getSelection().toString().length, 0);
+        })
+        testCancelledMouseMoveSelect.done();
+      });
+
+    }
+</script>
+
--- a/third_party/blink/renderer/core/input/event_handler.cc
+++ b/third_party/blink/renderer/core/input/event_handler.cc
@@ -980,7 +980,11 @@ WebInputEventResult EventHandler::HandleMouseMoveOrLeaveEvent(
  event_result = DispatchMousePointerEvent(
      WebInputEvent::kPointerMove, mev.InnerNode(), mev.CanvasRegionId(),
      mev.Event(), coalesced_events);
-  if (event_result != WebInputEventResult::kNotHandled)
+  // https://w3c.github.io/uievents/#event-type-mousemove
+  // Since there is no default action for the mousemove event issue a
+  // mouse dragged event irrespective of whether the event is cancelled.
+  if (event_result != WebInputEventResult::kNotHandled &&
+      event_result != WebInputEventResult::kHandledApplication)
    return event_result;

  return mouse_event_manager_->HandleMouseDraggedEvent(mev);