[sensors] Fix flakiness in generic sensors tests

third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp

Index: third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp
diff --git a/third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp b/third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp
index b2309114253196c350bd7826deba6e89434ab4e1..de85ce72ad14a2a4948e843ec87c2053d6c1931c 100644
--- a/third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp
+++ b/third_party/WebKit/Source/modules/sensor/SensorProviderProxy.cpp
@@ -14,6 +14,13 @@ namespace blink {
 
 // SensorProviderProxy
 SensorProviderProxy::SensorProviderProxy(LocalFrame* frame) {
+  initializeSensorProviderIfNeeded(frame);
+}
+
+void SensorProviderProxy::initializeSensorProviderIfNeeded(LocalFrame* frame) {
+  if (m_sensorProvider)
+    return;
+
   frame->interfaceProvider()->getInterface(mojo::GetProxy(&m_sensorProvider));
   m_sensorProvider.set_connection_error_handler(convertToBaseCallback(
       WTF::bind(&SensorProviderProxy::onSensorProviderConnectionError,
@@ -31,6 +38,8 @@ SensorProviderProxy* SensorProviderProxy::from(LocalFrame* frame) {
   if (!result) {
     result = new SensorProviderProxy(frame);
     Supplement<LocalFrame>::provideTo(*frame, supplementName(), result);
+  } else {
+    result->initializeSensorProviderIfNeeded(frame);

[Mikhail, 2016/11/28 10:42:51]

maybe split methods, like "isInitialized() const" + "initialize()", like we have
for SensorProxy. Then,

if (!provider->isInitialized())
   provider->initialize()

and call 'initialize()' from ctor.

[shalamov, 2016/11/28 12:50:54]

Done.

   }
   return result;
 }
@@ -66,6 +75,11 @@ SensorProxy* SensorProviderProxy::getSensorProxy(
   return nullptr;
 }
 
+device::mojom::blink::SensorProvider* SensorProviderProxy::getSensorProvider()

[Mikhail, 2016/11/28 10:42:51]

why move it here (and rename)? IMO it's fine to keep it inline.

[shalamov, 2016/11/28 12:50:54]

Wanted to make lazy getter, but then noticed that frame is required. Forgot to
move it back.

Done.

+    const {
+  return m_sensorProvider.get();
+}
+
 void SensorProviderProxy::onSensorProviderConnectionError() {
   if (!Platform::current()) {
     // TODO(rockot): Clean this up once renderer shutdown sequence is fixed.