Initial refactor to get profiles to propagate storage partition details.

chrome/browser/extensions/browser_tag_browsertest.cc

Index: chrome/browser/extensions/browser_tag_browsertest.cc
diff --git a/chrome/browser/extensions/browser_tag_browsertest.cc b/chrome/browser/extensions/browser_tag_browsertest.cc
index 460cb5b483aa2b3e51d95cbdf9d0ed37b08bb25a..fdd9401af19d2d5bee956627374c879b9e7d8799 100644
--- a/chrome/browser/extensions/browser_tag_browsertest.cc
+++ b/chrome/browser/extensions/browser_tag_browsertest.cc
@@ -100,15 +100,17 @@ IN_PROC_BROWSER_TEST_F(BrowserTagTest, Isolation) {
                               &cookie_size, &cookie_value);
   EXPECT_EQ("testCookie=1", cookie_value);
 
-  // Now, test the browser tags to ensure we have properly set the cookie and
-  // we have only one per browser tag and they are not the same.
+  // The default behavior is to combine browser tags with no explicit partition
+  // declaration into the same in-memory partition. Test the browser tags to
+  // ensure we have properly set the cookies and we have both cookies in both
+  // browser tags.
   automation_util::GetCookies(GURL("http://localhost"),
                               source1->GetWebContents(),
                               &cookie_size, &cookie_value);
-  EXPECT_EQ("guest1=true", cookie_value);
+  EXPECT_EQ("guest1=true; guest2=true", cookie_value);
 
   automation_util::GetCookies(GURL("http://localhost"),
                               source2->GetWebContents(),
                               &cookie_size, &cookie_value);
-  EXPECT_EQ("guest2=true", cookie_value);
+  EXPECT_EQ("guest1=true; guest2=true", cookie_value);
 }