Fix lines joining of TextDiagnostics on Windows

The initial assumption were that inside compiler and test framework all
line breaks are normalized, because we read text files only through IDEA
utils (which do normalization).

The mistake was that 'StringBuilder.appendln()' appends
'System.lineSeparator()' as well, so it's not enough to only check that
we don't load files from disk without normalizing whitespaces.

Note that using 'it.replace(System.lineSeparator(), ...)' would be
incorrect too, because actually we have strings with two kinds of line
breaks here (normalized and not normalized), so we're looking for both
via simple regex.

compiler/frontend/src/org/jetbrains/kotlin/checkers/diagnostics/TextDiagnostic.kt

@@ -81,7 +81,7 @@ class TextDiagnostic(
 
         if (renderParameters && parameters != null) {
             result.append("(")
-            result.append(StringUtil.join(parameters, { "\"${it.replace('\n', ' ')}\"" }, ", "))
+            result.append(StringUtil.join(parameters, { "\"" + crossPlatformLineBreak.matcher(it).replaceAll(" ") + "\"" }, ", "))
             result.append(")")
         }
         return result.toString()
@@ -92,6 +92,8 @@ class TextDiagnostic(
     }
 
     companion object {
+        private val crossPlatformLineBreak = Pattern.compile("""\r?\n""")
+
         fun parseDiagnostic(text: String): TextDiagnostic {
             val matcher = CheckerTestUtil.individualDiagnosticPattern.matcher(text)
             if (!matcher.find())