Bug 1420589 Part9: Dispatch pointer events to the capturing target even it's frame is destroyed. r=smaug.

MozReview-Commit-ID: DxNx3ByTdCW
2017-11-30 16:10:03 +08:00 · 2017-11-30 16:10:03 +08:00 · a4f6e53467
--- a/dom/events/PointerEventHandler.cpp
+++ b/dom/events/PointerEventHandler.cpp
@ -331,8 +331,8 @@ PointerEventHandler::GetPointerCapturingContent(uint32_t aPointerId)
  return nullptr;
 }

-/* static */ nsIFrame*
-PointerEventHandler::GetPointerCapturingFrame(WidgetGUIEvent* aEvent)
+/* static */ nsIContent*
+PointerEventHandler::GetPointerCapturingContent(WidgetGUIEvent* aEvent)
 {
  if (!IsPointerEventEnabled() || (aEvent->mClass != ePointerEventClass &&
                                   aEvent->mClass != eMouseEventClass) ||
@ -346,17 +346,7 @@ PointerEventHandler::GetPointerCapturingFrame(WidgetGUIEvent* aEvent)
  if (!mouseEvent) {
    return nullptr;
  }
-
-  // Find the content which captures the pointer.
-  nsIContent* capturingContent =
-    GetPointerCapturingContent(mouseEvent->pointerId);
-
-  if (!capturingContent) {
-    return nullptr;
-  }
-  // Return the content's primary frame as the target frame.
-  nsIFrame* capturingFrame = capturingContent->GetPrimaryFrame();
-  return capturingFrame ? capturingFrame : nullptr;
+  return GetPointerCapturingContent(mouseEvent->pointerId);
 }

 /* static */ void
--- a/dom/events/PointerEventHandler.h
+++ b/dom/events/PointerEventHandler.h
@ -89,17 +89,16 @@ public:
  static void ImplicitlyReleasePointerCapture(WidgetEvent* aEvent);

  /**
-   * GetPointerCapturingFrame returns a target frame of aEvent. If the event is
-   * a mouse or pointer event (except mousedown and pointerdown), the pointer
-   * may be captured by a content. This method returns the capturing content's
-   * primary frame. Otherwise, nullptr.
+   * GetPointerCapturingContent returns a target content which captures the
+   * pointer. It's applied to mouse or pointer event (except mousedown and
+   * pointerdown). When capturing, return the content. Otherwise, nullptr.
   *
   * @param aEvent               A mouse event or pointer event which may be
   *                             captured.
   *
-   * @return                     Target frame for aEvent.
+   * @return                     Target content for aEvent.
   */
-  static nsIFrame* GetPointerCapturingFrame(WidgetGUIEvent* aEvent);
+  static nsIContent* GetPointerCapturingContent(WidgetGUIEvent* aEvent);

  static nsIContent* GetPointerCapturingContent(uint32_t aPointerId);

--- a/dom/events/test/pointerevents/mochitest.ini
+++ b/dom/events/test/pointerevents/mochitest.ini
@ -145,6 +145,7 @@ support-files =
  support-files =
    file_test_trigger_fullscreen.html
 [test_trigger_popup_by_pointer_events.html]
+[test_remove_frame_when_got_pointer_capture.html]
 [test_getCoalescedEvents.html]
  skip-if = !e10s
  support-files =
--- a/dom/events/test/pointerevents/test_remove_frame_when_got_pointer_capture.html
+++ b/dom/events/test/pointerevents/test_remove_frame_when_got_pointer_capture.html
@ -0,0 +1,116 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Test for triggering popup by pointer events</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <script src="/tests/SimpleTest/EventUtils.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<div id="div1" style="width: 50px; height: 50px; background: green"></div>
+<div id="div2" style="width: 50px; height: 50px; background: green"></div>
+<script>
+
+SimpleTest.waitForExplicitFinish();
+
+function startTest() {
+  let div1 = document.getElementById("div1");
+  let divEvents = [
+    "pointerdown",
+    "gotpointercapture",
+    "pointermove",
+    "pointerup",
+    "lostpointercapture",
+    "mousedown",
+    "mousemove",
+    "mouseup",
+  ];
+
+  let documentEvents = [
+    "pointerdown",
+    "pointermove",
+    "pointerup",
+    "mousedown",
+    "mousemove",
+    "mouseup",
+  ];
+
+  divEvents.forEach((event) => {
+    div1.addEventListener(event, (e) => {
+      ok(divEvents.indexOf(e.type) >= 0, " don't expect " + e.type);
+      divEvents = divEvents.filter(item => item !== e.type);
+    }, { once: true });
+  });
+
+  documentEvents.forEach((event) => {
+    document.addEventListener(event, (e) => {
+      is(e.target, div1, e.type + " should be dispatched to div1");
+    }, { once: true });
+  });
+
+  div1.addEventListener("pointerdown", (e) => {
+    div1.setPointerCapture(e.pointerId);
+  });
+
+  div1.addEventListener("gotpointercapture", (e) => {
+    div1.style.display = "none";
+  });
+
+  synthesizeMouseAtCenter(div1, {type: "mousedown"});
+  synthesizeMouseAtCenter(div2, {type: "mousemove"});
+  synthesizeMouseAtCenter(div2, {type: "mouseup"});
+
+  ok(divEvents.length == 0, " expect " + divEvents);
+
+  divEvents = [
+    "pointerdown",
+    "gotpointercapture",
+    "pointermove",
+    "pointerup",
+    "lostpointercapture",
+    "touchstart",
+    "touchmove",
+    "touchend",
+  ];
+
+  documentEvents = [
+    "pointerdown",
+    "pointermove",
+    "pointerup",
+    "touchstart",
+    "touchmove",
+    "touchend",
+  ];
+  divEvents.forEach((event) => {
+    div1.addEventListener(event, (e) => {
+      ok(divEvents.indexOf(e.type) >= 0, " don't expect " + e.type);
+      divEvents = divEvents.filter(item => item !== e.type);
+    }, { once: true });
+  });
+
+  documentEvents.forEach((event) => {
+    document.addEventListener(event, (e) => {
+      is(e.target, div1, e.type + " should be dispatched to div1");
+    }, { once: true });
+  });
+
+  div1.style.display = "block";
+  synthesizeMouseAtCenter(div1, {type: "mousemove"});
+  synthesizeTouch(div1, 5, 5, { type: "touchstart" });
+  synthesizeTouch(div2, 5, 5, { type: "touchmove" });
+  synthesizeTouch(div2, 5, 5, { type: "touchend" });
+
+  ok(divEvents.length == 0, " expect " + divEvents);
+  SimpleTest.finish();
+}
+
+SimpleTest.waitForFocus(() => {
+  SpecialPowers.pushPrefEnv({
+    "set": [["dom.w3c_pointer_events.enabled", true]]
+  }, startTest);
+});
+
+</script>
+</body>
+</html>
--- a/layout/base/PresShell.cpp
+++ b/layout/base/PresShell.cpp
@ -7188,11 +7188,35 @@ PresShell::HandleEvent(nsIFrame* aFrame,
      }
    }

-    nsIFrame* pointerCapturingFrame =
-      PointerEventHandler::GetPointerCapturingFrame(aEvent);
+    // Only capture mouse events and pointer events.
+    nsIContent* pointerCapturingContent =
+      PointerEventHandler::GetPointerCapturingContent(aEvent);

-    if (pointerCapturingFrame) {
-      frame = pointerCapturingFrame;
+    if (pointerCapturingContent) {
+      nsIFrame* pointerCapturingFrame =
+        pointerCapturingContent->GetPrimaryFrame();
+
+      if (!pointerCapturingFrame) {
+        // Dispatch events to the capturing content even it's frame is
+        // destroyed.
+        PointerEventHandler::DispatchPointerFromMouseOrTouch(
+          this, nullptr, pointerCapturingContent, aEvent, false, aEventStatus,
+          nullptr);
+
+        PresShell* shell = GetShellForEventTarget(nullptr,
+                                                  pointerCapturingContent);
+
+        if (!shell) {
+          // The capturing element could be changed when dispatch pointer
+          // events.
+          return NS_OK;
+        }
+        return shell->HandleEventWithTarget(aEvent, nullptr,
+                                            pointerCapturingContent,
+                                            aEventStatus, true);
+      } else {
+        frame = pointerCapturingFrame;
+      }
    }

    WidgetMouseEvent* mouseEvent = aEvent->AsMouseEvent();
@ -7204,7 +7228,8 @@ PresShell::HandleEvent(nsIFrame* aFrame,
    // be used instead below. Also keep using the root frame if we're dealing
    // with a window-level mouse exit event since we want to start sending
    // mouse out events at the root EventStateManager.
-    if (!captureRetarget && !isWindowLevelMouseExit && !pointerCapturingFrame) {
+    if (!captureRetarget && !isWindowLevelMouseExit &&
+        !pointerCapturingContent) {
      if (aEvent->mClass == eTouchEventClass) {
        frame = TouchManager::SetupTarget(aEvent->AsTouchEvent(), frame);
      } else {
@ -7228,7 +7253,7 @@ PresShell::HandleEvent(nsIFrame* aFrame,
    // retargeted at the capturing content instead. This will be the case when
    // capture retargeting is being used, no frame was found or the frame's
    // content is not a descendant of the capturing content.
-    if (capturingContent && !pointerCapturingFrame &&
+    if (capturingContent && !pointerCapturingContent &&
        (gCaptureInfo.mRetargetToElement || !frame->GetContent() ||
         !nsContentUtils::ContentIsCrossDocDescendantOf(frame->GetContent(),
                                                        capturingContent))) {