fix: bail if directory isn't writable

Since we can't exit from common.js, create an error code
and exit from the test runner instead.

test/common.js

@@ -70,7 +70,7 @@ exports.refreshTmpDir = function() {
     fs.accessSync(testRoot, fs.W_OK);
   } catch (e) {
     if (e.code === 'ENOENT') {
-      fs.mkdirSync(testRoot);
+      process.exit(101);
     }
   }
 

tools/test.py

@@ -152,6 +152,11 @@ def RunSingle(self, parallel, thread_id):
       if self.shutdown_event.is_set():
         return
       self.lock.acquire()
+      if output.ShouldExit():
+        self.lock.release()
+        PrintError("\nThe temporary folder you specified doesn't exist or" \
+              " can't be written to. Take necessary actions and try again")
+        os._exit(1)
       if output.UnexpectedOutput():
         if FLAKY in output.test.outcomes and self.flaky_tests_mode == DONTCARE:
           self.flaky_failed.append(output)
@@ -497,6 +502,9 @@ def __init__(self, test, command, output, store_unexpected_output):
     self.store_unexpected_output = store_unexpected_output
     self.diagnostic = []
 
+  def ShouldExit(self):
+    return self.output.exit_code == 101
+
   def UnexpectedOutput(self):
     if self.HasCrashed():
       outcome = CRASH