The new config is now used for perf measurements. The old
ones are deleted to avoid redundancy.

This also ports https://codereview.chromium.org/754523004 to the new config file.

BUG=chromium:374740
LOG=n
TBR=ulan@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/782673003

Cr-Commit-Position: refs/heads/master@{#25674}

The big change here is to split out each key type into its own
benchmark suite, since optimizations for different key types
are likely to be disjoint. ForEach tests have also been split
into separate "Iteration" suites, again with the thought that
iteration performance is likely separable from key type.

As part of adding the new tests, rejiggered the existing tests:
  - Map.set and Set.add (along with their Weak variants) no longer
    include construction costs in their scores
  - Moved key logic into the shared common.js

R=arv@chromium.org, machenbach@chromium.org

Review URL: https://codereview.chromium.org/685753004

Cr-Commit-Position: refs/heads/master@{#24969}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24969 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUG=
R=dslomov@chromium.org

Review URL: https://codereview.chromium.org/667373004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24806 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

Also small reformat in Iterators/forof.js

R=machenbach@chromium.org

Review URL: https://codereview.chromium.org/662723006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24682 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

TBR=dslomov@chromium.org, bmeurer@chromium.org

Review URL: https://codereview.chromium.org/641033003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24493 ce2b1a6d-e550-0410-aec6-3dcde31c8c00