Add gdbinit to tools/ directory.

Suggested usage: echo "source /path/to/v8/tools/gdbinit" >> ~/.gdbinit

R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/375503009

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22252 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
MIPS: Only create arguments-maps in the bootstrapper, remove now obsolete ValueType flag.

Port r22245 (1471c64)

BUG=
R=palfia@homejinni.com

Review URL: https://codereview.chromium.org/375603002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22253 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Hydrogenized KeyedLoadGeneric stub: when probing the KeyedLookupCache fails, call the runtime, don't stub-fail.

R=danno@chromium.org

Review URL: https://codereview.chromium.org/367343002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22254 ce2b1a6d-e550-0410-aec6-3dcde31c8c00