requestIdleCallback: Yield for high priority work

third_party/WebKit/Source/core/dom/IdleDeadline.cpp

Index: third_party/WebKit/Source/core/dom/IdleDeadline.cpp
diff --git a/third_party/WebKit/Source/core/dom/IdleDeadline.cpp b/third_party/WebKit/Source/core/dom/IdleDeadline.cpp
index f35300d57e5c330cf16c747342813ead8df10a5f..8a6345b65d03589048595a4a7a9f14c04141afef 100644
--- a/third_party/WebKit/Source/core/dom/IdleDeadline.cpp
+++ b/third_party/WebKit/Source/core/dom/IdleDeadline.cpp
@@ -5,6 +5,8 @@
 #include "core/dom/IdleDeadline.h"
 
 #include "core/timing/PerformanceBase.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebScheduler.h"
 #include "wtf/CurrentTime.h"
 
 namespace blink {
@@ -13,6 +15,13 @@ IdleDeadline::IdleDeadline(double deadlineSeconds, CallbackType callbackType)
     : m_deadlineSeconds(deadlineSeconds), m_callbackType(callbackType) {}
 
 double IdleDeadline::timeRemaining() const {
+  if (Platform::current()
+          ->currentThread()
+          ->scheduler()
+          ->shouldYieldForHighPriorityWork()) {
+    return 0;
+  }

[rmcilroy, 2016/11/18 09:13:51]

nit - how about just setting timeRemaining to zero, and only doing the check I'd
timeRemaining != 0?

[Sami, 2016/11/21 11:28:02]

Good idea, done.

+
   double timeRemaining = m_deadlineSeconds - monotonicallyIncreasingTime();
   if (timeRemaining < 0)
     timeRemaining = 0;