[gcc 4.8] Remove multi-line comment to avoid build break due to -Werror=comment

TBR=rockot@chromium.org, asargent@chromium.org
NOTRY=true

BUG=399251

Review URL: https://codereview.chromium.org/447113002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@288008 0039d316-1c4b-4281-b951-d872f2087c98

extensions/browser/computed_hashes_unittest.cc

@@ -78,7 +78,7 @@ TEST(ComputedHashes, ComputedHashes) {
 // The file with multiple-blocks expectations were generated by doing:
 // $ for i in `seq 500 ; do printf "hello world" ; done > hello.txt
 // $ dd if=hello.txt bs=4096 count=1 | openssl dgst -sha256 -binary | base64
-// $ dd if=hello.txt skip=1 bs=4096 count=1 | \
+// $ dd if=hello.txt skip=1 bs=4096 count=1 |
 //   openssl dgst -sha256 -binary | base64
 TEST(ComputedHashes, ComputeHashesForContent) {
   const int block_size = 4096;