RFR: 8282685: fileToEncodedURL_[name|signature] symbols are unused

[Calvin Cheung]

A simple fix for removing two unused symbols from vmSymbols.hpp.

Passed CI tier1 testing.

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Commit messages:
 - 8282685: fileToEncodedURL_[name|signature] symbols are unused

Changes: https://git.openjdk.java.net/jdk/pull/7965/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7965&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8282685
  Stats: 2 lines in 1 file changed: 0 ins; 2 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7965.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7965/head:pull/7965

PR: https://git.openjdk.java.net/jdk/pull/7965