BufferHub{Buffer,Metadata}: Some other minor changes

1/ Move BufferHubMetadata out of android::dvr namespace
2/ Fix some misnamed variables

Bug: 111976433
Test: BufferHubBuffer_test
Change-Id: I06ec1c3cc4831c865b672680b49adb006d6e1835
diff --git a/libs/ui/BufferHubMetadata.cpp b/libs/ui/BufferHubMetadata.cpp
index b0c4510..1e08ed1 100644
--- a/libs/ui/BufferHubMetadata.cpp
+++ b/libs/ui/BufferHubMetadata.cpp
@@ -22,7 +22,6 @@
 #include <ui/BufferHubMetadata.h>
 
 namespace android {
-namespace dvr {
 
 namespace {
 
@@ -30,8 +29,8 @@
 
 } // namespace
 
-using BufferHubDefs::kMetadataHeaderSize;
-using BufferHubDefs::MetadataHeader;
+using dvr::BufferHubDefs::kMetadataHeaderSize;
+using dvr::BufferHubDefs::MetadataHeader;
 
 /* static */
 BufferHubMetadata BufferHubMetadata::Create(size_t userMetadataSize) {
@@ -101,5 +100,4 @@
     }
 }
 
-} // namespace dvr
 } // namespace android