Most Visited: remove over-eager optimization that causes a lot of blank thumbnails

Most Visited: remove over-eager optimization that causes a lot of blank thumbnails

after storing thumbnails in the thread safe cache, we were removing those which are not currently in the top 8. This sucks because then when you blacklist a site, the thumbnail for the replacement is not in the cache, so we use a default image even though the thumbnail is available in the DB. The optimization hardly saves us anything, as the number of cached thumbnails is capped to begin with, and we are only trimming to 8, and it's ref counted data anyway so it's already resident somewhere else in memory either way.

BUG=none
TEST=blacklist a site. Most likely you will get an actual thumbnail for its replacement


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=106559

[sky, 2011-10-20 16:39:49]

LGTM

[Evan Stade, 2011-10-20 18:15:03]

updated (fixed test and removed dead code)

[sky, 2011-10-20 18:29:46]

LGTM

[commit-bot: I haz the power, 2011-10-20 18:46:55]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/estade@chromium.org/8355031/4001

[commit-bot: I haz the power, 2011-10-20 20:19:13]

Change committed as 106559