Write the command to execute in the error message so people don't have to learn how svn works.
Write the command to execute in the error message so people don't have to learn how svn works.

TEST=none
BUG=none

Review URL: http://codereview.chromium.org/126050

git-svn-id: bd64dd6fa6f3f0ed0c0666d1018379882b742947@18273 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

svn2github/chromium-depot-tools,svn2github/chromium-depot-tools,svn2github/chromium-depot-tools