Fix test failure problem in non-English environment

[kmizu]

• For example, tests which expect some javac's error messages fail in Japanese environment
  since the error messages are localized in such a environment

[lyricallogical]

Some additional explanations...

Currently, A neg test "neg/t6289" is checked by a javac's error message. It depend locale of user's environment. It is necessary to fix a javac's error message to english.
JDK tools uses system properties instead of environment variables for locale, e.g. LANG, LC_CTYPE, and LC_ALL.
Ok, in partest, java commands run with options "-Duser.lanugage=en -Duser.country=US".

scala-partest/src/main/scala/scala/tools/partest/nest/Runner.scala

Lines 170 to 171 in 047cb32

	"-Duser.language=en",
	"-Duser.country=US"

Unfortunately, the javac command does not.

scala-partest/src/main/scala/scala/tools/partest/nest/Runner.scala

Lines 104 to 120 in 1c78ce6

	def javac(files: List[File]): TestState = {
	// compile using command-line javac compiler
	val args = Seq(
	javacCmdPath,
	"-d",
	outDir.getAbsolutePath,
	"-classpath",
	joinPaths(outDir :: testClassPath)
	) ++ files.map(_.getAbsolutePath)
	pushTranscript(args mkString " ")
	val captured = StreamCapture(runCommand(args, logFile))
	if (captured.result) genPass() else {
	logFile appendAll captured.stderr
	genFail("java compilation failed")
	}
	}

In current implementation, there is no smart way for passing options to javac that run for tests.

Please fix this for contributors in outside of english language regions.

[kmizu]

@SethTisue Please review this pull request.

[SethTisue]

@szeiger you've been up in partest recently, would you mind reviewing this one?

[szeiger]

I think this needs to be US. Language codes are lowercase, country codes are upper case (like in propertyOptions in the same file)

[kmizu]

@szeiger Thanks for reviewing. I fixed the mistake you point out

[szeiger]

Great, LGTM otherwise. Please squash the commits (no need to wait for the current build of the separate commit).

[kmizu]

@szeiger Thanks. I squashed the commits.

[SethTisue]

good catch — thank you for the fix!