Cleanup namespace usage in public/platform/{Web[P-W]*,linux/*}.h

public/platform/WebRTCSessionDescriptionRequest.h

Index: public/platform/WebRTCSessionDescriptionRequest.h
diff --git a/public/platform/WebRTCSessionDescriptionRequest.h b/public/platform/WebRTCSessionDescriptionRequest.h
index 8e17f56239c6299d9062e6a3fafbd841757a8330..2aa46e68b54adad943b059aebbcd60c1f94fd544 100644
--- a/public/platform/WebRTCSessionDescriptionRequest.h
+++ b/public/platform/WebRTCSessionDescriptionRequest.h
@@ -37,10 +37,8 @@
 #include "WebString.h"
 
 namespace blink {
-class RTCSessionDescriptionRequest;
-}
 
-namespace blink {
+class RTCSessionDescriptionRequest;
 class WebRTCSessionDescription;
 
 class WebRTCSessionDescriptionRequest {
@@ -76,11 +74,11 @@ public:
     BLINK_PLATFORM_EXPORT void setExtraData(ExtraData*);
 
 #if INSIDE_BLINK
-    BLINK_PLATFORM_EXPORT WebRTCSessionDescriptionRequest(const WTF::PassRefPtr<blink::RTCSessionDescriptionRequest>&);
+    BLINK_PLATFORM_EXPORT WebRTCSessionDescriptionRequest(const WTF::PassRefPtr<RTCSessionDescriptionRequest>&);
 #endif
 
 private:
-    WebPrivatePtr<blink::RTCSessionDescriptionRequest> m_private;
+    WebPrivatePtr<RTCSessionDescriptionRequest> m_private;
 };
 
 } // namespace blink