Add PPAPI style enums to V2 IDL parser

Adds the ability to process
  identifier
     or
  identifier = ConstValue

and removes
  string

from Enums for Pepper IDL.

BUG=224150
TEST=PRESUBMIT or ./run_tests.py
R=nfullagar@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=209454

[noelallen1, 2013-06-29 20:09:15]

ptal

[nfullagar1, 2013-07-01 17:22:13]

https://codereview.chromium.org/18273002/diff/1/tools/idl_parser/test_parser/...
File tools/idl_parser/test_parser/enum_ppapi.idl (right):

https://codereview.chromium.org/18273002/diff/1/tools/idl_parser/test_parser/...
tools/idl_parser/test_parser/enum_ppapi.idl:115: noodles = 0x1 << 0x2,
what is expected outcome for octal?

[noelallen1, 2013-07-01 17:46:06]

https://codereview.chromium.org/18273002/diff/1/tools/idl_parser/test_parser/...
File tools/idl_parser/test_parser/enum_ppapi.idl (right):

https://codereview.chromium.org/18273002/diff/1/tools/idl_parser/test_parser/...
tools/idl_parser/test_parser/enum_ppapi.idl:115: noodles = 0x1 << 0x2,
On 2013/07/01 17:22:13, nfullagar1 wrote:
> what is expected outcome for octal?

Octal should be legal, although we never use it.  I can add a test case for it
here.

The lexer distinguishes between boolean, int, float, and string literals, but
does not distinguish between base 8, 10, or 16, they are all ints.

The parser never computes values of expressions, simply determines that the
expression is a valid int and adds a property pair to the EnumItem:
  TYPE = "integer"
  VALUE = "1", "1.0", "123", "0x123" or even "1 << 1"

[nfullagar1, 2013-07-01 17:53:46]

thx for adding the test, lgtm

[noelallen1, 2013-07-01 17:56:26]

Committed patchset #2 manually as r209454 (presubmit successful).