Partial rollback of commit dd142c9.

Should fix bazelbuild#2721.

--
PiperOrigin-RevId: 150866145
MOS_MIGRATED_REVID=150866145

src/main/java/com/google/devtools/build/lib/exec/TestStrategy.java

@@ -286,18 +286,9 @@ protected TestCase parseTestResult(Path resultFile) {
    * --test_tmpdir. This does not create the directory.
    */
   public static Path getTmpRoot(Path workspace, Path execRoot, ExecutionOptions executionOptions) {
-    if (executionOptions.testTmpDir != null) {
-      return workspace.getRelative(executionOptions.testTmpDir).getRelative(TEST_TMP_ROOT);
-    }
-    switch (OS.getCurrent()) {
-      case WINDOWS:
-        // TODO(philwo) find a better way to do this
-        // Hardcoding this to c:/temp isn't great, but if we use a longer path, we trip the MAX_PATH
-        // limit of the Windows API when running bazel inside shell integration tests.
-        return workspace.getFileSystem().getPath("c:/temp");
-      default:
-        return execRoot.getRelative(TEST_TMP_ROOT);
-    }
+    return executionOptions.testTmpDir != null
+        ? workspace.getRelative(executionOptions.testTmpDir).getRelative(TEST_TMP_ROOT)
+        : execRoot.getRelative(TEST_TMP_ROOT);
   }
 
   /**