Convert the pp::proxy namespace to the ppapi::proxy namespace.

ppapi/proxy/host_dispatcher_unittest.cc

Index: ppapi/proxy/host_dispatcher_unittest.cc
diff --git a/ppapi/proxy/host_dispatcher_unittest.cc b/ppapi/proxy/host_dispatcher_unittest.cc
index 14dfed5699c1dc251540e589975f3b332538c973..25dfa5c1bcfe9ee7920cef94b8421633c5a62012 100644
--- a/ppapi/proxy/host_dispatcher_unittest.cc
+++ b/ppapi/proxy/host_dispatcher_unittest.cc
@@ -9,9 +9,7 @@
 #include "ppapi/proxy/ppapi_messages.h"
 #include "ppapi/proxy/ppapi_proxy_test.h"
 
-using ppapi::HostResource;
-
-namespace pp {
+namespace ppapi {
 namespace proxy {
 
 class HostDispatcherTest : public HostProxyTest {
@@ -40,5 +38,5 @@ TEST_F(HostDispatcherTest, FAILS_PPBCreation) {
 }
 
 }  // namespace proxy
-}  // namespace pp
+}  // namespace ppapi