Re-enable previously flaky ChromeRenderProcessHostTest tests after bl…

…ocker's resolution.

The Backgrounding test was disabled in issue 394368 but the remaining blocker was just fixed
in issue 460357.

Also try to re-enable ProcessPerTab, ProcessOverflow, and ProcessOverflowCommandLine which may
or may not have suffered from the same issue (locally they pass today in >50 retries in parallel..?).

BUG=394368, 442785
TBR=jochen@chromium.org

Review URL: https://codereview.chromium.org/1527213003

Cr-Commit-Position: refs/heads/master@{#365701}

chrome/browser/renderer_host/render_process_host_chrome_browsertest.cc

@@ -230,8 +230,8 @@ class ChromeRenderProcessHostTestWithCommandLine
   }
 };
 
-// Disable on Mac and Windows due to ongoing flakiness. (crbug.com/442785)
-#if defined(OS_MACOSX) || defined(OS_WIN)
+// Disable on Mac due to ongoing flakiness. (crbug.com/442785)
+#if defined(OS_MACOSX)
 #define MAYBE_ProcessPerTab DISABLED_ProcessPerTab
 #else
 #define MAYBE_ProcessPerTab ProcessPerTab
@@ -297,13 +297,7 @@ IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, MAYBE_ProcessPerTab) {
 // We don't change process priorities on Mac or Posix because the user lacks the
 // permission to raise a process' priority even after lowering it.
 #if defined(OS_WIN) || defined(OS_LINUX)
-#if defined(OS_WIN)
-// Flaky test: crbug.com/394368
-#define MAYBE_Backgrounding DISABLED_Backgrounding
-#else
-#define MAYBE_Backgrounding Backgrounding
-#endif
-IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, MAYBE_Backgrounding) {
+IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, Backgrounding) {
   if (!base::Process::CanBackgroundProcesses()) {
     LOG(ERROR) << "Can't background processes";
     return;
@@ -353,7 +347,7 @@ IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, MAYBE_Backgrounding) {
 
 // TODO(nasko): crbug.com/173137
 // Disable on Mac 10.9 due to ongoing flakiness. (crbug.com/442785)
-#if defined(OS_WIN) || defined(OS_MACOSX)
+#if defined(OS_MACOSX)
 #define MAYBE_ProcessOverflow DISABLED_ProcessOverflow
 #else
 #define MAYBE_ProcessOverflow ProcessOverflow
@@ -366,10 +360,10 @@ IN_PROC_BROWSER_TEST_F(ChromeRenderProcessHostTest, MAYBE_ProcessOverflow) {
 }
 
 // Disable on Mac 10.9 due to ongoing flakiness. (crbug.com/442785)
-#if defined(OS_MACOSX) || defined(OS_WIN)
-#define MAYBE_ProcessOverflowCommandLine DISABLED_ProcessOverflow
+#if defined(OS_MACOSX)
+#define MAYBE_ProcessOverflowCommandLine DISABLED_ProcessOverflowCommandLine
 #else
-#define MAYBE_ProcessOverflowCommandLine ProcessOverflow
+#define MAYBE_ProcessOverflowCommandLine ProcessOverflowCommandLine
 #endif
 
 // Variation of the ProcessOverflow test, which is driven through command line