Move Google Cache copy suggestion to an action button in the neterror interstitial

chrome/common/localized_error.cc

Index: chrome/common/localized_error.cc
diff --git a/chrome/common/localized_error.cc b/chrome/common/localized_error.cc
index 0c4ad4361e590adf71d4784a78846863e490b287..500ae2b21704c2c10b56709ac529d5c94f96df61 100644
--- a/chrome/common/localized_error.cc
+++ b/chrome/common/localized_error.cc
@@ -7,6 +7,7 @@
 #include "base/command_line.h"
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
+#include "base/metrics/field_trial.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ -56,6 +57,11 @@ static const char kAppWarningLearnMoreUrl[] =
     "chrome-extension://honijodknafkokifofgiaalefdiedpko/main.html"
     "?answer=1721911";
 #endif  // defined(OS_CHROMEOS)
+static const char kCachedCopyButtonFieldTrial[] =
+    "enable_google_cached_copy_text_experiment";
+static const char kCachedCopyButtonExpTypeControl[] = "control";
+static const char kCachedCopyButtonExpTypeCopy[] = "copy";
+static const char kCachedCopyButtonExpTypePage[] = "page";
 
 enum NAV_SUGGESTIONS {
   SUGGEST_NONE                  = 0,
@@ -671,6 +677,42 @@ void LocalizedError::GetStrings(int error_code,
   } else {
     suggestions = params->override_suggestions.release();
     use_default_suggestions = false;
+
+    std::string fieldTrialExpType =
+        base::FieldTrialList::FindFullName(kCachedCopyButtonFieldTrial);
+
+    // If the first suggestion is for a Google cache copy. Promote the
+    // suggestion to a separate set of strings for displaying as a button.
+    if (!suggestions->empty() && !fieldTrialExpType.empty() &&
+        fieldTrialExpType != kCachedCopyButtonExpTypeControl) {
+      base::DictionaryValue* suggestion;
+      suggestions->GetDictionary(0, &suggestion);
+      int type = -1;
+      suggestion->GetInteger("type", &type);
+
+      if (type == 0) {
+        base::string16 cache_url;
+        suggestion->GetString("urlCorrection", &cache_url);
+        int cache_tracking_id = -1;
+        suggestion->GetInteger("trackingId", &cache_tracking_id);
+
+        base::DictionaryValue* cache_button = new base::DictionaryValue;
+
+        if (fieldTrialExpType == kCachedCopyButtonExpTypeCopy) {
+          cache_button->SetString("msg",
+                                  l10n_util::GetStringUTF16(
+                                      IDS_ERRORPAGES_BUTTON_SHOW_CACHED_COPY));
+        } else if (fieldTrialExpType == kCachedCopyButtonExpTypePage) {

[felt, 2015/05/12 14:15:08]

You might have had the right idea with the else branch before, since now if the
Finch code returns something unexpected this code won't set anything for "msg".
A few ideas:

* an else branch that DCHECKs
* an else branch with a default msg
* move the "page" condition back into a plain else branch but with a comment
saying it is for "page"

[edwardjung, 2015/05/13 09:59:56]

Reverted back to using the else statement

+          cache_button->SetString("msg",
+                                  l10n_util::GetStringUTF16(
+                                      IDS_ERRORPAGES_BUTTON_SHOW_CACHED_PAGE));
+        }
+        cache_button->SetString("cacheUrl", cache_url);
+        cache_button->SetInteger("trackingId", cache_tracking_id);
+        error_strings->Set("cacheButton", cache_button);
+        suggestions->Remove(0, NULL);
+      }
+    }
   }
 
   error_strings->Set("suggestions", suggestions);