Cleanup namespace ending comment

(This is a merge of http://go/wvgerrit/13400 from the Widevine CDM
repository.)

Replace "};  // namespace" with "}  // namespace":
ag -l --ignore-dir third_party "};  //" | \
while read f; do sed -r -i 's/\};  \/\//}  \/\//' $f ; done

Replace "// unnamed namespace" with "// namespace":
ag -l --ignore-dir third_party "unnamed namespace" | \
while read f; do sed -r -i 's/unnamed namespace/namespace/' $f ; done

Change-Id: I50ece9a127ce669f15cd532dfae1dd741338a075

libwvdrmengine/cdm/core/include/string_conversions.h

@@ -24,6 +24,6 @@ std::string UintToString(unsigned int value);
 int64_t htonll64(int64_t x);
 int64_t ntohll64(int64_t x);
 
-};  // namespace wvcdm
+}  // namespace wvcdm
 
 #endif  // WVCDM_CORE_STRING_CONVERSIONS_H_