[AdTagging] Make a filter tool test deterministic

The MatchRules test had non-deterministic sorting behavior on
different platforms. Fix this by avoiding situations in the test where
there are ties for the number of matches.

Bug: 878328, 877148
Change-Id: I4883141c0c5c8ab02ace9365b4a446f132d6cea1
Reviewed-on: https://chromium-review.googlesource.com/1193902
Commit-Queue: Josh Karlin <jkarlin@chromium.org>
Commit-Queue: Charlie Harrison <csharrison@chromium.org>
Reviewed-by: Charlie Harrison <csharrison@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586697}

components/subresource_filter/tools/filter_tool_unittest.cc

@@ -133,6 +133,11 @@ TEST_F(FilterToolTest, MatchRules) {
                                   "http://example.com/disallowed1.png", "image")
                 << CreateJsonLine("http://example.com",
                                   "http://example.com/disallowed2.png", "image")
+                << CreateJsonLine(
+                       "http://example.com",
+                       "http://example.com/whitelist/disallowed2.png", "image")
+                << CreateJsonLine("http://example.com",
+                                  "http://example.com/disallowed1.png", "image")
                 << CreateJsonLine(
                        "http://example.com",
                        "http://example.com/whitelist/disallowed2.png", "image");
@@ -142,8 +147,8 @@ TEST_F(FilterToolTest, MatchRules) {
   std::string result = out_stream_.str();
 
   std::string expected =
-      "2 disallowed1.png|\n"
-      "1 @@whitelist/disallowed2.png|\n"
+      "3 disallowed1.png|\n"
+      "2 @@whitelist/disallowed2.png|\n"
       "1 disallowed2.png|\n";
 
   EXPECT_EQ(expected, out_stream_.str());