Make IDB RenderThreadShutdownTest non-single-process.

The IndexedDBBrowserTestSingleProcess.RenderThreadShutdownTest
was already disabled on Android and ASAN. The test has flakes
on MacOS, Linux and TSAN as well. Rather than just disabling,
convert it to being a non-single-process test as that's not
a realistic configuration. The test is kept around although
likely the render process is simply terminated so it's not
testing much.

Bug: 368901, 788788, 1065523
Change-Id: If31017da91f50f91f1ff677fcdd78d08d075a3eb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2134930Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Commit-Queue: Joshua Bell <jsbell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#756727}

content/browser/indexed_db/indexed_db_browsertest.cc

@@ -1180,21 +1180,7 @@ IN_PROC_BROWSER_TEST_F(IndexedDBBrowserTestV2SchemaCorruption, LifecycleTest) {
   SimpleTest(embedded_test_server()->GetURL(test_file));
 }
 
-class IndexedDBBrowserTestSingleProcess : public IndexedDBBrowserTest {
- public:
-  void SetUpCommandLine(base::CommandLine* command_line) override {
-    command_line->AppendSwitch(switches::kSingleProcess);
-  }
-};
-
-// https://crbug.com/788788
-#if defined(OS_ANDROID) && defined(ADDRESS_SANITIZER)
-#define MAYBE_RenderThreadShutdownTest DISABLED_RenderThreadShutdownTest
-#else
-#define MAYBE_RenderThreadShutdownTest RenderThreadShutdownTest
-#endif  // defined(OS_ANDROID) && defined(ADDRESS_SANITIZER)
-IN_PROC_BROWSER_TEST_F(IndexedDBBrowserTestSingleProcess,
-                       MAYBE_RenderThreadShutdownTest) {
+IN_PROC_BROWSER_TEST_F(IndexedDBBrowserTest, ShutdownWithRequests) {
   SimpleTest(GetTestUrl("indexeddb", "shutdown_with_requests.html"));
 }