Rework timeline/frame scheduling logic for SVGImage

third_party/WebKit/Source/core/svg/graphics/SVGImageChromeClient.cpp

 /*
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 10 matching lines @@
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/svg/graphics/SVGImageChromeClient.h"
 
-#include "core/frame/FrameView.h"
 #include "core/svg/graphics/SVGImage.h"
-#include "platform/ScriptForbiddenScope.h"
 #include "platform/graphics/ImageObserver.h"
 #include "wtf/CurrentTime.h"
 
 namespace blink {
 
 static const double animationFrameDelay = 0.025;
 
 SVGImageChromeClient::SVGImageChromeClient(SVGImage* image)
     : m_image(image)
     , m_animationTimer(this, &SVGImageChromeClient::animationTimerFired)
+    , m_timelineState(Running)
 {
 }
 
 SVGImageChromeClient* SVGImageChromeClient::create(SVGImage* image)
 {
     return new SVGImageChromeClient(image);
 }
 
 bool SVGImageChromeClient::isSVGImageChromeClient() const
 {
     return true;
 }
 
 void SVGImageChromeClient::chromeDestroyed()
 {
     m_image = nullptr;
 }
 
 void SVGImageChromeClient::invalidateRect(const IntRect& r)
 {
     // If m_image->m_page is null, we're being destructed, don't fire changedInRect() in that case.
     if (m_image && m_image->getImageObserver() && m_image->m_page)
         m_image->getImageObserver()->changedInRect(m_image, r);
 }
 
+void SVGImageChromeClient::suspendAnimation()
+{
+    // Preserve SuspendedWithFramePending if set.
+    m_timelineState = std::max(m_timelineState, Suspended);
+}
+
+void SVGImageChromeClient::resumeAnimation()
+{
+    bool havePendingFrame = m_timelineState == SuspendedWithFramePending;
+    m_timelineState = Running;
+
+    // If an animation frame was requested while animations were blocked, kick
+    // off an animation timer right away.
+    if (!havePendingFrame)
+        return;
+    // In the unlikely event that we suspend and resume within a single frame,
+    // the timer could still be running, so just leave it at the current
+    // timeout.
+    if (m_animationTimer.isActive())

[chrishtr, 2016/05/20 18:26:15]

Why not just call scheduleAnimation() directly? The Widget parameter is unused
anyway.

[fs, 2016/05/20 19:23:58]

That would schedule a timer with a delay of |animationFrameDelay| rather than 0.

[chrishtr, 2016/05/20 19:55:18]

Does that matter?

[fs, 2016/05/20 20:03:06]

I guess we can try it and see.

[chrishtr, 2016/05/23 20:02:51]

I suppose it doesn't matter that much. Only a few lines of code.

[fs, 2016/05/23 20:58:34]

I've shuffled this around a bit now, and this is now calling scheduleAnimation
directly.

+        return;
+    m_animationTimer.startOneShot(0, BLINK_FROM_HERE);
+}
+
 void SVGImageChromeClient::scheduleAnimation(Widget*)
 {
     // Because a single SVGImage can be shared by multiple pages, we can't key
     // our svg image layout on the page's real animation frame. Therefore, we
     // run this fake animation timer to trigger layout in SVGImages. The name,
     // "animationTimer", is to match the new requestAnimationFrame-based layout
     // approach.
     if (m_animationTimer.isActive())
         return;
     // Schedule the 'animation' ASAP if the image does not contain any
     // animations, but prefer a fixed, jittery, frame-delay if there're any
     // animations. Checking for pending/active animations could be more
     // stringent.
-    double fireTime = m_image->hasAnimations() ? animationFrameDelay : 0;
+    double fireTime = 0;
+    if (m_image->hasAnimations()) {
+        if (m_timelineState >= Suspended) {
+            m_timelineState = SuspendedWithFramePending;
+            return;
+        }
+        fireTime = animationFrameDelay;
+    }
     m_animationTimer.startOneShot(fireTime, BLINK_FROM_HERE);
 }
 
 void SVGImageChromeClient::animationTimerFired(Timer<SVGImageChromeClient>*)
 {
     if (!m_image)
         return;
 
     // The SVGImageChromeClient object's lifetime is dependent on
     // the ImageObserver (an ImageResource) of its image. Should it
     // be dead and about to be lazily swept out, do not proceed.
     //
     // TODO(Oilpan): move (SVG)Image to the Oilpan heap, and avoid
     // this explicit lifetime check.
     if (ThreadHeap::willObjectBeLazilySwept(m_image->getImageObserver()))
         return;
 
-    // serviceScriptedAnimations runs requestAnimationFrame callbacks, but SVG
-    // images can't have any so we assert there's no script.
-    ScriptForbiddenScope forbidScript;
-
-    // The calls below may trigger GCs, so set up the required persistent
-    // reference on the ImageResource which owns this SVGImage. By transitivity,
-    // that will keep this SVGImageChromeClient object alive.
-    Persistent<ImageObserver> protect(m_image->getImageObserver());
-    m_image->frameView()->page()->animator().serviceScriptedAnimations(monotonicallyIncreasingTime());
-    m_image->frameView()->updateAllLifecyclePhases();
+    m_image->serviceAnimations(monotonicallyIncreasingTime());
 }
 
 } // namespace blink