Linux: Handle renderer and plugin crashes on a separate thread. (try 2)...

Linux: Handle renderer and plugin crashes on a separate thread. (try 2)

Also set retries / timeouts for wget to attempt to limit the duration of each crash handler.
Move some code out of headers while we're at it.

BUG=54071
TEST=change /usr/bin/wget to sleep forever, visit about:crash in a Breakpad-enabled build, make sure other renderers continue to work.
Original Review URL: http://codereview.chromium.org/3308007

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=58431

[Lei Zhang, 2010-09-02 22:37:19]

Whoops, I forgot to make this work without Breakpad. Added some trivial changes
to crash_handler_host_linux_stub.cc and a few #ifdefs to
crash_handler_host_linux.h.

[willchan no longer on Chromium, 2010-09-02 22:51:19]

OK