Avoid global using namespace statements in modules/sensor

global using namespace statements cause issues with jumbo builds so this
patch moves and removes two such occurances in modules/sensor.

An alternative is to import explicit symbols rather than the full
namespaces.

R=mikhail.pozdnyakov@intel.com

Bug: 
Change-Id: Iafc85a856b02b381dae6244b2fc3acedc37e30db
Reviewed-on: https://chromium-review.googlesource.com/565296Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: bratell at Opera <bratell@opera.com>
Cr-Commit-Position: refs/heads/master@{#485277}

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

@@ -14,8 +14,6 @@
 #include "modules/sensor/SensorProviderProxy.h"
 #include "services/device/public/interfaces/sensor.mojom-blink.h"
 
-using namespace device::mojom::blink;
-
 namespace blink {
 
 namespace {
@@ -28,7 +26,7 @@ constexpr double kMinWaitingInterval =
 Sensor::Sensor(ExecutionContext* execution_context,
                const SensorOptions& sensor_options,
                ExceptionState& exception_state,
-               SensorType type)
+               device::mojom::blink::SensorType type)
     : ContextLifecycleObserver(execution_context),
       sensor_options_(sensor_options),
       type_(type),

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

@@ -11,10 +11,10 @@
 #include "platform/mojo/MojoHelper.h"
 #include "public/platform/Platform.h"
 
-using namespace device::mojom::blink;
-
 namespace blink {
 
+using namespace device::mojom::blink;
+
 SensorProxy::SensorProxy(SensorType sensor_type,
                          SensorProviderProxy* provider,
                          Page* page)