Remaining changes to build all code in src.git with -Wimplicit-fallthrough.

Fixes a bug where TaskManagerTester::GetColumnValue() would return the
ColumnSpecifier::TOTAL_NETWORK_USE value for ColumnSpecifier::NETWORK_USE.

Change a test that was relying on the broken behavior to query
TOTAL_NETWORK_USE instead of NETWORK_USE, which also happens to fix
a TODO in that test.

This CL was uploaded by git cl split.

R=afakhry@chromium.org

Bug: 177475
Change-Id: I1c146e4f60c41f024a0f32f0924b4d0811a9a620
Reviewed-on: https://chromium-review.googlesource.com/891885
Commit-Queue: Nico Weber <thakis@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532927}

chrome/browser/task_manager/providers/child_process_task.cc

@@ -94,6 +94,7 @@ base::string16 GetLocalizedTitle(const base::string16& title,
         return l10n_util::GetStringFUTF16(IDS_TASK_MANAGER_RENDERER_PREFIX,
                                           result_title);
       }
+      FALLTHROUGH;
     }
     // These types don't need display names or get them from elsewhere.
     case content::PROCESS_TYPE_BROWSER:

chrome/browser/task_manager/task_manager_browsertest.cc

@@ -698,12 +698,8 @@ IN_PROC_BROWSER_TEST_F(TaskManagerBrowserTest, SentDataObserved) {
       ->GetActiveWebContents()
       ->GetMainFrame()
       ->ExecuteJavaScriptForTests(base::UTF8ToUTF16(test_js));
-  // TODO(cburn): The assertion below currently assumes that the rate
-  // contribution of the entire 16MB upload arrives in a single refresh cycle.
-  // That's true now because it's only reported when the transaction completes,
-  // but if that changes in the future, this assertion may need to change.
   ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerStatToExceed(
-      MatchTab("network use"), ColumnSpecifier::NETWORK_USE, 16000000));
+      MatchTab("network use"), ColumnSpecifier::TOTAL_NETWORK_USE, 16000000));
 }
 
 IN_PROC_BROWSER_TEST_F(TaskManagerBrowserTest, TotalSentDataObserved) {

chrome/browser/task_manager/task_manager_tester.cc

@@ -168,6 +168,7 @@ int64_t TaskManagerTester::GetColumnValue(ColumnSpecifier column, int row) {
     case ColumnSpecifier::NETWORK_USE:
       value = task_manager()->GetNetworkUsage(task_id);
       success = true;
+      break;
     case ColumnSpecifier::TOTAL_NETWORK_USE:
       value = task_manager()->GetCumulativeNetworkUsage(task_id);
       success = true;