Get rid of 'close' on process. It is very easy to use incorrectly and cut off data from your stream…

utils/testrunner/layout_test_controller.dart

Index: utils/testrunner/layout_test_controller.dart
diff --git a/utils/testrunner/layout_test_controller.dart b/utils/testrunner/layout_test_controller.dart
index d8864a3d681f9742033e90df3ffe352f721d561b..8dedf11d1874bc8b451b1afe8216629d617eeca7 100644
--- a/utils/testrunner/layout_test_controller.dart
+++ b/utils/testrunner/layout_test_controller.dart
@@ -129,6 +129,8 @@ runTextLayoutTest(testNum) {
   var stdout = new List();
   start = new Date.now();
   Process.start(drt, [url]).then((process) {
+    // Drain stderr to not leak resources.
+    process.stderr.onData = process.stderr.read;
     StringInputStream stdoutStringStream =
         new StringInputStream(process.stdout);
     stdoutStringStream.onLine = () {
@@ -213,6 +215,8 @@ runPixelLayoutTest(int testNum) {
   var stdout = new List();
   start = new Date.now();
   Process.start(drt, ["$url'-p"]).then((process) {
+    // Drain stderr to not leak resources.
+    process.stderr.onData = process.stderr.read;
     ListInputStream stdoutStream = process.stdout;
     stdoutStream.onData = () {
       if (!stdoutStream.closed) {