RFR: 8284920: Incorrect Token type causes XPath expression to return incorrect results [v2]

[Joe Wang]

> Patch note:
> 
> The previous patch changed all literal tokens to use constants. However, replacing "." with Token.DOT introduced this bug. 
> While tokens with a single char are inherently of type char, due to the different implementation of the overloaded method "tokenIs" that takes String or char, a wrong input type will produce incorrect result. It may be worth it to take a closer look at the overloaded method, but for now, a quick fix is to reverse the input type back to String (DOT_STR).
> 
> Test: the issue affect the processing of the short form of the parent axis "..". The test verifies that all form of the parent axis shall return the same result.
> 
> Test: all XML tests passed.

Joe Wang has updated the pull request incrementally with one additional commit since the last revision:

  add test cases for the self axis

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8321/files
  - new: https://git.openjdk.java.net/jdk/pull/8321/files/cb5e5ec3..3b61789e

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8321&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8321&range=00-01

  Stats: 12 lines in 1 file changed: 11 ins; 0 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8321.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8321/head:pull/8321

PR: https://git.openjdk.java.net/jdk/pull/8321