[Sensors] Improvements in shared buffer managing

third_party/WebKit/Source/modules/sensor/SensorProxy.h

Index: third_party/WebKit/Source/modules/sensor/SensorProxy.h
diff --git a/third_party/WebKit/Source/modules/sensor/SensorProxy.h b/third_party/WebKit/Source/modules/sensor/SensorProxy.h
index 70c87a2f15b4b5e194ef350aa14f311c55b13fa3..05c7c446b6f7d8a58ec576cd661ee3a616593ddb 100644
--- a/third_party/WebKit/Source/modules/sensor/SensorProxy.h
+++ b/third_party/WebKit/Source/modules/sensor/SensorProxy.h
@@ -6,6 +6,7 @@
 #define SensorProxy_h
 
 #include "core/dom/ExceptionCode.h"
+#include "device/generic_sensor/public/cpp/sensor_reading.h"
 #include "device/generic_sensor/public/interfaces/sensor.mojom-blink.h"
 #include "device/generic_sensor/public/interfaces/sensor_provider.mojom-blink.h"
 #include "mojo/public/cpp/bindings/binding.h"
@@ -60,13 +61,7 @@ class SensorProxy final : public GarbageCollectedFinalized<SensorProxy>,
   device::mojom::blink::SensorType type() const { return m_type; }
   device::mojom::blink::ReportingMode reportingMode() const { return m_mode; }
 
-  struct Reading {
-    double timestamp;
-    double reading[3];
-  };
-  static_assert(sizeof(Reading) ==
-                    device::mojom::blink::SensorInitParams::kReadBufferSize,
-                "Check reading size");
+  using Reading = device::SensorReading;
 
   const Reading& reading() const { return m_reading; }
 
@@ -93,6 +88,8 @@ class SensorProxy final : public GarbageCollectedFinalized<SensorProxy>,
   void onSensorCreated(device::mojom::blink::SensorInitParamsPtr,
                        device::mojom::blink::SensorClientRequest);
 
+  bool tryReadFromBuffer();
+
   device::mojom::blink::SensorType m_type;
   device::mojom::blink::ReportingMode m_mode;
   Member<SensorProviderProxy> m_provider;
@@ -109,6 +106,11 @@ class SensorProxy final : public GarbageCollectedFinalized<SensorProxy>,
   mojo::ScopedSharedBufferMapping m_sharedBuffer;
   Reading m_reading;
   bool m_suspended;
+  using ReadingBuffer = device::SensorReadingSharedBuffer;
+  static_assert(
+      sizeof(ReadingBuffer) ==
+          device::mojom::blink::SensorInitParams::kReadBufferSizeForTests,
+      "Check reading buffer size for tests");
 };
 
 }  // namespace blink