Make the rebaseline log server resilient to large logs.

Make the rebaseline log server resilient to large logs.

Right now when it exceeds the appengine storage limit for a single
entry it 500s. Instead, just create a new entry. This isn't totally
ideal. Ideally we'd create a new entry but link it to the old
one so we can show it correctly in the UI, but that's too much work.

NOTRY=true
BUG=378490
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175230

[Dirk Pranke, 2014-06-01 21:02:21]

lgtm

[ojan, 2014-06-01 23:19:31]

The CQ bit was checked by ojan@chromium.org

[commit-bot: I haz the power, 2014-06-01 23:19:42]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/ojan@chromium.org/304303003/1

[commit-bot: I haz the power, 2014-06-01 23:20:19]

Change committed as 175230