Use FrameIsAd to decide whether to isolate a frame in TopDocumentIsolation mode.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 805f11498046df3ef11cb5e4f63fab9fd4f63496..70a9d607d1dd1f2822b91e52900a52d2d79b7e46 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -1078,6 +1078,27 @@ const FeatureEntry::FeatureVariation kOmniboxUIVerticalMarginVariations[] = {
     {"14px vertical margin", kOmniboxUIVerticalMargin14px,
      arraysize(kOmniboxUIVerticalMargin14px), nullptr}};
 
+const char kTopDocumentIsolationVariations_Ads_Value[] = {
+    '0' + static_cast<int>(features::TopDocumentIsolationMode::Ads), '\0'};

[Łukasz Anforowicz, 2017/06/30 15:28:36]

My opinion is that the code above is better than 1) hardcoding "1" (or was it
"2") here and/or 2) introducing ugly C++ templates (e.g. see
https://repl.it/JJAt/0).  FWIW, I am asking for a second opinion at
cxx@chromium.org DL
(https://groups.google.com/a/chromium.org/d/topic/cxx/W4pyzIQ1ksc/discussion).

[Charlie Reis, 2017/06/30 23:28:45]

Looks like you got this resolved.

+const FeatureEntry::FeatureParam kTopDocumentIsolationVariations_Ads[] = {
+    {features::kTopDocumentIsolationModeParam,
+     kTopDocumentIsolationVariations_Ads_Value}};
+
+const char kTopDocumentIsolationVariations_Xsite_Value[] = {
+    '0' + static_cast<int>(features::TopDocumentIsolationMode::Xsite), '\0'};
+const FeatureEntry::FeatureParam kTopDocumentIsolationVariations_Xsite[] = {
+    {features::kTopDocumentIsolationModeParam,
+     kTopDocumentIsolationVariations_Xsite_Value}};
+
+const FeatureEntry::FeatureVariation kTopDocumentIsolationVariations[] = {
+    {"(isolate ads detected by heuristics)",
+     kTopDocumentIsolationVariations_Ads,
+     arraysize(kTopDocumentIsolationVariations_Ads), nullptr},
+    {"(isolate all frames from site other than the top-level frame)",

[Łukasz Anforowicz, 2017/06/30 15:28:37]

The string above is concatenated with "Enabled " string.  See the CL description
for the 5 variations/options that this CL makes available for
TopDocumentIsolation's entry in chrome://flags. 

+     kTopDocumentIsolationVariations_Xsite,
+     arraysize(kTopDocumentIsolationVariations_Xsite), nullptr},
+};
+
 // RECORDING USER METRICS FOR FLAGS:
 // -----------------------------------------------------------------------------
 // The first line of the entry is the internal name.
@@ -1936,7 +1957,9 @@ const FeatureEntry kFeatureEntries[] = {
     {"enable-top-document-isolation",
      flag_descriptions::kTopDocumentIsolationName,
      flag_descriptions::kTopDocumentIsolationDescription, kOsAll,
-     FEATURE_VALUE_TYPE(features::kTopDocumentIsolation)},
+     FEATURE_WITH_PARAMS_VALUE_TYPE(features::kTopDocumentIsolation,
+                                    kTopDocumentIsolationVariations,
+                                    "TopDocumentIsolation")},
     {"enable-use-zoom-for-dsf", flag_descriptions::kEnableUseZoomForDsfName,
      flag_descriptions::kEnableUseZoomForDsfDescription, kOsAll,
      MULTI_VALUE_TYPE(kEnableUseZoomForDSFChoices)},