[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 9e41bd3a56bb3ccf5cfecc56dc02410bf4f824f2..82e5e3164160bf45792ddb1a54681c32d2d88a8f 100644
--- a/third_party/WebKit/Source/modules/sensor/SensorProxy.h
+++ b/third_party/WebKit/Source/modules/sensor/SensorProxy.h
@@ -5,6 +5,7 @@
 #ifndef SensorProxy_h
 #define SensorProxy_h
 
+#include "device/base/synchronization/shared_memory_seqlock_buffer.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"
@@ -57,13 +58,7 @@ 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::mojom::blink::SensorReading;
 
   const Reading& reading() const { return m_reading; }
 
@@ -104,6 +99,7 @@ class SensorProxy final : public GarbageCollectedFinalized<SensorProxy>,
   mojo::ScopedSharedBufferMapping m_sharedBuffer;
   Reading m_reading;
   bool m_suspended;
+  using ReadingBuffer = device::SharedMemorySeqLockBuffer<Reading>;
 };
 
 }  // namespace blink