Move PerformanceBase to TaskRunnerTimer.

third_party/WebKit/Source/core/timing/PerformanceBase.cpp

Index: third_party/WebKit/Source/core/timing/PerformanceBase.cpp
diff --git a/third_party/WebKit/Source/core/timing/PerformanceBase.cpp b/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
index ba4eb8ffdf5b8ff275b06936b7f6d46435c7dfc3..56b483ab38a210a0bec60bacb403af346bc259f6 100644
--- a/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
+++ b/third_party/WebKit/Source/core/timing/PerformanceBase.cpp
@@ -66,13 +66,15 @@ using PerformanceObserverVector = HeapVector<Member<PerformanceObserver>>;
 static const size_t defaultResourceTimingBufferSize = 150;
 static const size_t defaultFrameTimingBufferSize = 150;
 
-PerformanceBase::PerformanceBase(double timeOrigin)
+PerformanceBase::PerformanceBase(double timeOrigin,
+                                 RefPtr<WebTaskRunner> taskRunner)
     : m_frameTimingBufferSize(defaultFrameTimingBufferSize),
       m_resourceTimingBufferSize(defaultResourceTimingBufferSize),
       m_userTiming(nullptr),
       m_timeOrigin(timeOrigin),
       m_observerFilterOptions(PerformanceEntry::Invalid),
       m_deliverObservationsTimer(
+          std::move(taskRunner),

[haraken, 2017/01/20 02:21:51]

What is making it hard to unconditionally use
TaskRunnerHelper::get(TaskType::PerformanceTimeline) here?

[jbroman, 2017/01/20 02:27:04]

PerformanceBase doesn't have any object to pass to TaskRunnerHelper. And it's
the base class also of WorkerPerformance, so LocalFrame and Document don't
apply.

ExecutionContext could possibly be used, but we don't actually need the whole
ExecutionContext, and currently some of the test implementations return nullptr
from their override of getExecutionContext.
It seems better, then, to have the derived class be responsible for choosing the
arguments to pass to TaskRunnerHelper. The only subclass for which that's
currently very meaningful is Performance (the main-thread version).

           this,
           &PerformanceBase::deliverObservationsTimerFired) {}