Override cache policy when changing a reload to a back/forward navigation.

chrome/browser/crash_recovery_browsertest.cc

Index: chrome/browser/crash_recovery_browsertest.cc
diff --git a/chrome/browser/crash_recovery_browsertest.cc b/chrome/browser/crash_recovery_browsertest.cc
index fcde2cb825f748de6fb31e2cb43ceecc3d4161cd..a8adcaf2bfb0413f6657fe3fa9852c60ab585fa0 100644
--- a/chrome/browser/crash_recovery_browsertest.cc
+++ b/chrome/browser/crash_recovery_browsertest.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/files/file_path.h"
+#include "base/strings/stringprintf.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_commands.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
@@ -13,6 +14,9 @@
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/page_transition_types.h"
+#include "net/test/embedded_test_server/embedded_test_server.h"
+#include "net/test/embedded_test_server/http_request.h"
+#include "net/test/embedded_test_server/http_response.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using content::NavigationController;
@@ -31,6 +35,32 @@ void SimulateRendererCrash(Browser* browser) {
   observer.Wait();
 }
 
+// A request handler which is set to expire in the far future, but returns a
+// different result each time.
+class CacheExpiresHandler {
+ public:
+  explicit CacheExpiresHandler(const std::string& path)
+      : path_(path), request_count_(0) { }
+
+  scoped_ptr<net::test_server::HttpResponse> HandleRequest(
+      const net::test_server::HttpRequest& request) {
+    if (request.relative_url != path_)
+      return scoped_ptr<net::test_server::HttpResponse>();
+
+    request_count_++;
+    scoped_ptr<net::test_server::BasicHttpResponse> response(
+        new net::test_server::BasicHttpResponse);
+    response->set_content(base::StringPrintf("<title>%d</title>",
+                                             request_count_));
+    response->set_content_type("text/html");
+    response->AddCustomHeader("Expires", "Thu, 1 Jan 2099 00:00:00 GMT");

[darin (slow to review), 2014/01/07 07:39:59]

nit: another approach here would be to set a cache-control header with
max-age=99999 or some other big number. that way you don't have to invent a
fixed time in the way way future.

[davidben, 2014/01/08 17:38:03]

Ah yeah, that would be better. Done.

+    return response.PassAs<net::test_server::HttpResponse>();
+  }
+ private:
+  std::string path_;
+  int request_count_;
+};
+
 }  // namespace
 
 class CrashRecoveryBrowserTest : public InProcessBrowserTest {
@@ -62,6 +92,37 @@ IN_PROC_BROWSER_TEST_F(CrashRecoveryBrowserTest, Reload) {
   EXPECT_NE(title_before_crash, title_after_crash);
 }
 
+// Test that reload after a crash forces a cache revalidation.
+IN_PROC_BROWSER_TEST_F(CrashRecoveryBrowserTest, ReloadCacheRevalidate) {
+  const char kTestPath[] = "/test";
+
+  // Use the test server so as not to bypass cache behavior. The title of the
+  // active tab should change only when this URL is reloaded.
+  ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());
+  embedded_test_server()->RegisterRequestHandler(
+      base::Bind(&CacheExpiresHandler::HandleRequest,
+                 base::Owned(new CacheExpiresHandler(kTestPath))));
+  ui_test_utils::NavigateToURL(browser(),
+                               embedded_test_server()->GetURL(kTestPath));
+
+  base::string16 title_before_crash;
+  base::string16 title_after_crash;
+
+  ASSERT_TRUE(ui_test_utils::GetCurrentTabTitle(browser(),
+                                                &title_before_crash));
+  SimulateRendererCrash(browser());
+  content::WindowedNotificationObserver observer(
+      content::NOTIFICATION_LOAD_STOP,
+      content::Source<NavigationController>(
+          &browser()->tab_strip_model()->GetActiveWebContents()->
+              GetController()));
+  chrome::Reload(browser(), CURRENT_TAB);
+  observer.Wait();
+  ASSERT_TRUE(ui_test_utils::GetCurrentTabTitle(browser(),
+                                                &title_after_crash));
+  EXPECT_NE(title_before_crash, title_after_crash);
+}
+
 // Tests that loading a crashed page in a new tab correctly updates the title.
 // There was an earlier bug (1270510) in process-per-site in which the max page
 // ID of the RenderProcessHost was stale, so the NavigationEntry in the new tab