Integrated: JDK-8264664: use text blocks in javac module tests

[Jonathan Gibbons]

Please review an update to the javac module tests to use text blocks to represent multi-line strings.

The conversion was done mostly semi-automatically, using a utility used to covert the javadoc tests. Some edits were manual.

In all cases, there are no changes to the semantics of any test. In particular, no diagnostic messages containing line and column information were updated.

All `:tier1` tests pass on all standard platforms.

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Commit messages:
 - fix whitespace issues
 - JDK-8264664: use text blocks in javac module tests

Changes: https://git.openjdk.java.net/jdk/pull/3335/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3335&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8264664
  Stats: 632 lines in 18 files changed: 127 ins; 0 del; 505 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3335.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3335/head:pull/3335

PR: https://git.openjdk.java.net/jdk/pull/3335