ServiceWorker: Remove iframes explicitly after a test is finished

third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js

Index: third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js b/third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
index 65215669d63e267a851f047b4f28bd4b1e3cc650..a45f85a25b3365f084fec177aea8a3b7dbc00110 100644
--- a/third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
+++ b/third_party/WebKit/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
@@ -44,14 +44,16 @@ function unreached_rejection(test, prefix) {
 }
 
 // Adds an iframe to the document and returns a promise that resolves to the
-// iframe when it finishes loading. The caller is responsible for removing the
-// iframe later if needed.
-function with_iframe(url) {
+// iframe when it finishes loading. By default, the caller is responsible for

[nhiroki, 2016/04/06 07:46:35]

"By default" sounds a bit unclear. Can you elaborate the meaning of
|reclaim_after_completion|? For example,

// iframe when it finishes loading. If |reclaim_after_completion| is true,
registers a completion callback to remove the frame. Otherwise, the caller is
responsible for removing the iframe later.

[falken, 2016/04/06 07:49:05]

Drive-by comment: How about making reclaim_after_completion the default
behavior? Also I'd slightly prefer passing some const value instead of
true/false for readability.

[shimazu (google), 2016/04/07 04:17:59]

Done.

+// removing the iframe later if needed.
+function with_iframe(url, reclaim_after_completion) {
   return new Promise(function(resolve) {
       var frame = document.createElement('iframe');
       frame.src = url;
       frame.onload = function() { resolve(frame); };
       document.body.appendChild(frame);
+      if (reclaim_after_completion)

[nhiroki, 2016/04/06 07:46:35]

if (reclaim_after_compleation === true)

... could be more stable in JS.

[shimazu (google), 2016/04/07 04:17:59]

Done.

+        add_completion_callback(function() { frame.remove(); });
     });
 }