Avoid repeating code when creating builtins.

Avoid repeating code when creating builtins.

InstallBuiltinFunctionIds stood out when looking at code that grew
strangely when compiled with default optimizations.

This change from repeated code to a loop saves 6-7 KB of machine code.
I suspect it's faster but I also suspect it's fast enough either way so
that is not really a factor. Machine code reduction seen below.

Code formatted with git cl format.

clang x64:
Total change: -5985 bytes
-------------------------------------------
 +517 - Source: ?? - (gained 744, lost 227)
-------------------------------------------
  New symbols:
       +744: v8::internal::Genesis::InstallBuiltinFunctionIds()::builtins type=d, size=744 bytes
  Removed symbols:
         -4: .L.str98 type=r, size=4 bytes
... [stripped 30 similar lines]
        -19: .L.str100 type=r, size=19 bytes

----------------------------------------------------------------------------------------------
 -6502 - Source: /home/bratell/src/chromium/src/v8/src/bootstrapper.cc - (gained 0, lost 6502)
----------------------------------------------------------------------------------------------
  Removed symbols:
      -1135: v8::internal::ResolveBuiltinIdHolder(v8::internal::Handle<v8::internal::Context>, char const*) type=t, size=1135 bytes
  Shrunk symbols:
      -5367: v8::internal::Genesis::InstallBuiltinFunctionIds() type=t, (was 7105 bytes, now 1738 bytes)

BUG=

Committed: https://crrev.com/bd21d72d507625e5caf70f31ee11c8c21ead1651
Cr-Commit-Position: refs/heads/master@{#26919}

[Daniel Bratell, 2015-02-19 15:39:46]

bratell@opera.com changed reviewers:
+ dslomov@chromium.org

[Daniel Bratell, 2015-02-19 15:39:47]

dslomov, can you please take a look. Not high priority, just random cleanup.

And git cl did the formatting. :-/

[Dmitry Lomov (no reviews), 2015-02-26 14:20:12]

lgtm, sorry for delay

[Daniel Bratell, 2015-02-27 14:49:27]

The CQ bit was checked by bratell@opera.com

[commit-bot: I haz the power, 2015-02-27 14:50:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/918303005/1

[commit-bot: I haz the power, 2015-02-27 15:21:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-02-27 15:22:00]

Patchset 1 (id:??) landed as
https://crrev.com/bd21d72d507625e5caf70f31ee11c8c21ead1651
Cr-Commit-Position: refs/heads/master@{#26919}