plumb network upload into the task manager

chrome/browser/task_manager/task_manager_browsertest.cc

Index: chrome/browser/task_manager/task_manager_browsertest.cc
diff --git a/chrome/browser/task_manager/task_manager_browsertest.cc b/chrome/browser/task_manager/task_manager_browsertest.cc
index 51e133c5d75743e3fe9bdca0bb700e10838b202d..983cd20ac44cd0ff63dc519aaef35decba39bc48 100644
--- a/chrome/browser/task_manager/task_manager_browsertest.cc
+++ b/chrome/browser/task_manager/task_manager_browsertest.cc
@@ -672,6 +672,84 @@ IN_PROC_BROWSER_TEST_F(TaskManagerBrowserTest, JSHeapMemory) {
   ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, MatchTab("title1.html")));
 }
 
+IN_PROC_BROWSER_TEST_F(TaskManagerBrowserTest, SentDataObserved) {
+  ShowTaskManager();
+  GURL test_gurl = embedded_test_server()->GetURL("/title1.html");
+
+  ui_test_utils::NavigateToURL(browser(), test_gurl);
+  std::string test_js = R"(
+      mem = new Uint8Array(16 << 20);
+      for (var i = 0; i < mem.length; i += 16)
+        mem[i] = i;
+      var formData = new FormData();
+      formData.append('StringKey1', new Blob([mem]));
+      var request = new Request(
+            location.href,
+            {method: 'POST', body: formData});
+      fetch(request)
+          .then(response => response.text())
+          .then(body => domAutomationController.send("okay"))
+          .catch(error => domAutomationController.send("failed " + error));
+      )";
+  std::string ok;
+
+  ASSERT_TRUE(content::ExecuteScriptAndExtractString(
+      browser()->tab_strip_model()->GetActiveWebContents(), test_js, &ok));
+  ASSERT_EQ("okay", ok);
+
+  ASSERT_NO_FATAL_FAILURE(
+      WaitForTaskManagerStatToExceed(MatchTab(test_gurl.GetContent().c_str()),

[ncarter (slow), 2017/06/17 00:21:02]

Just use MatchTab("title1.html") -- it's consistent with what the existing tests
do.

[cburn, 2017/06/19 22:07:08]

Done.

+                                     ColumnSpecifier::NETWORK_USE, 16000000));

[ncarter (slow), 2017/06/17 00:21:02]

I worry that this might be flaky, for two reasons:

 - The upload is done by the time ExecuteScriptAndExtractString returns, so it's
possible that the TaskManager has already shown the network use and refreshed
again.
 - It seems like it would be incorrect if the network service actually gave us
regular reports, rather than all-at-once.

I think you can likely fix the first case (not the second) by means of the
following recipe:

1. Don't bother with the domAutomationController.send(). You just wait for the
TaskManager stat, so you don't a result at all.
2. Instead of content::ExecuteScript, use:

 
browser()->tab_strip_model()->GetActiveWebContents()->GetMainFrame()->ExecuteJavaScriptForTests(UTF8ToUTF16(script));

The difference is that this is a nonblocking call -- it doesn't run the message
loop waiting for the script to complete, it just sends a message to the renderer
and returns. (Look at the definition of content::ExecuteScript, and you'll see
it's implemented in terms of this function). So it's not possible for the
TaskManager's state to have changed in the interim, which means that you
couldn't have missed anything inside of WaitForStatToExeceed.

[cburn, 2017/06/19 22:07:08]

Done.

+}
+
+IN_PROC_BROWSER_TEST_F(TaskManagerBrowserTest, TotalSentDataObserved) {
+  ShowTaskManager();
+  GURL test_gurl = embedded_test_server()->GetURL("/title1.html");
+
+  ui_test_utils::NavigateToURL(browser(), test_gurl);
+  std::string test_js = R"(
+      mem = new Uint8Array(16 << 20);

[ncarter (slow), 2017/06/17 00:21:02]

"var mem ="

[cburn, 2017/06/19 22:07:08]

Done.

+      for (var i = 0; i < mem.length; i += 16)
+        mem[i] = i;
+      var formData = new FormData();
+      formData.append('StringKey1', new Blob([mem]));
+      var request = new Request(
+            location.href,
+            {method: 'POST', body: formData});
+      fetch(request)
+          .then(response => response.text())
+          .then(body => domAutomationController.send("okay"))
+          .catch(error => domAutomationController.send("failed " + error));
+      )";
+  std::string ok;
+
+  ASSERT_TRUE(content::ExecuteScriptAndExtractString(
+      browser()->tab_strip_model()->GetActiveWebContents(), test_js, &ok));
+  ASSERT_EQ("okay", ok);
+  test_js = R"(
+      mem = new Uint8Array(16 << 20);
+      for (var i = 0; i < mem.length; i += 16)
+        mem[i] = i;

[ncarter (slow), 2017/06/17 00:21:01]

mem already exists from the previous script execution, so you don't need to set
it up a second time.

[cburn, 2017/06/19 22:07:08]

Done.

+      var formData = new FormData();
+      formData.append('StringKey1', new Blob([mem]));
+      var request = new Request(
+            location.href,
+            {method: 'POST', body: formData});
+      setTimeout( function(){fetch(request)

[ncarter (slow), 2017/06/17 00:21:02]

Use lambda syntax here, since it's used elsewhere in the statement.

"function(){"  becomes "() => {"

[cburn, 2017/06/19 22:07:08]

Done.

+          .then(response => response.text())
+          .then(body => domAutomationController.send("okay"))
+          .catch(error => domAutomationController.send("failed " + error))},
+          2000);

[ncarter (slow), 2017/06/17 00:21:01]

What's the importance of this two-second wait? (Is it just to exceed the nyquist
ratio?)

If so, it's maybe worth documenting with a comment.

[cburn, 2017/06/19 22:07:08]

Done.

+      )";
+  ASSERT_TRUE(content::ExecuteScriptAndExtractString(
+      browser()->tab_strip_model()->GetActiveWebContents(), test_js, &ok));
+  ASSERT_EQ("okay", ok);
+
+  ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerStatToExceed(
+      MatchTab(test_gurl.GetContent().c_str()),
+      ColumnSpecifier::TOTAL_NETWORK_USE, 16000000 * 2));
+}
+
 // Checks that task manager counts idle wakeups.
 // Flakily fails on Mac: http://crbug.com/639939
 #if defined(OS_MACOSX)