base: Put md5.* into base namespace.

BUG=89274
TEST=None

[email protected]

Review URL: http://codereview.chromium.org/7395021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@92861 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/printing/image.cc b/printing/image.cc
index 062ac891..f9b177bf 100644
--- a/printing/image.cc
+++ b/printing/image.cc
@@ -50,8 +50,8 @@
 Image::~Image() {}
 
 std::string Image::checksum() const {
-  MD5Digest digest;
-  MD5Sum(&data_[0], data_.size(), &digest);
+  base::MD5Digest digest;
+  base::MD5Sum(&data_[0], data_.size(), &digest);
   return base::HexEncode(&digest, sizeof(digest));
 }