Set up Finch trial for malware download warnings

chrome/browser/download/download_item_model.cc

Index: chrome/browser/download/download_item_model.cc
diff --git a/chrome/browser/download/download_item_model.cc b/chrome/browser/download/download_item_model.cc
index b1c89fca2b294f477212fae55762f12646996472..900188b6f68a173c21aaf764449e9731e84ed82f 100644
--- a/chrome/browser/download/download_item_model.cc
+++ b/chrome/browser/download/download_item_model.cc
@@ -6,12 +6,14 @@
 
 #include "base/i18n/number_formatting.h"
 #include "base/i18n/rtl.h"
+#include "base/metrics/field_trial.h"
 #include "base/strings/string16.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/supports_user_data.h"
 #include "base/time/time.h"
 #include "chrome/browser/download/download_crx_util.h"
+#include "chrome/browser/download/download_util.h"
 #include "chrome/browser/safe_browsing/download_feedback_service.h"
 #include "content/public/browser/download_danger_type.h"
 #include "content/public/browser/download_interrupt_reasons.h"
@@ -301,12 +303,18 @@ string16 DownloadItemModel::GetWarningText(const gfx::Font& font,
                                            int base_width) const {
   // Should only be called if IsDangerous().
   DCHECK(IsDangerous());
+  std::string trial_condition =
+      base::FieldTrialList::FindFullName(download_util::kFinchTrialName);
   string16 elided_filename =
       ui::ElideFilename(download_->GetFileNameToReportUser(), font, base_width);
   switch (download_->GetDangerType()) {
     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_URL:

[Dan Beam, 2013/08/09 23:24:51]

arguably, you'd put |trial_condition| here and below as well...

here's the rule in the style guide, btw -
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Local_...

[felt, 2013/08/09 23:48:34]

I'd like to do this, but it causes compiler errors like this:

../../chrome/browser/download/download_danger_prompt.cc:127:19: error: jump to
case label [-fpermissive]
../../chrome/browser/download/download_danger_prompt.cc:115:19: error:   crosses
initialization of ‘std::string trial_condition’

because it's not inside a scope smaller than the switch (as it is in the webui
version).

[Dan Beam, 2013/08/10 00:08:49]

case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_URL: {  // <-- add curlies
}

[felt, 2013/08/10 00:33:00]

Done.

-      return l10n_util::GetStringUTF16(IDS_PROMPT_MALICIOUS_DOWNLOAD_URL);
-
+      if (trial_condition.empty()) {
+        return l10n_util::GetStringUTF16(IDS_PROMPT_MALICIOUS_DOWNLOAD_URL);
+      } else {
+        return download_util::AssembleMalwareFinchString(trial_condition,

[Dan Beam, 2013/08/10 00:13:56]

nit: also don't use else after an if + return, i.e.

  if (trial_condition.empty())
    return l10n_util::GetStringUTF16(IDS_PROMPT_MALICIOUS_DOWNLOAD_URL);

  return download_util::AssembleMalwareFinchString(trial_condition,
                                                   elided_filename);

[felt, 2013/08/10 00:33:00]

Done

+                                                         elided_filename);
+      }
     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_FILE:
       if (download_crx_util::IsExtensionDownload(*download_)) {
         return l10n_util::GetStringUTF16(
@@ -315,12 +323,15 @@ string16 DownloadItemModel::GetWarningText(const gfx::Font& font,
         return l10n_util::GetStringFUTF16(IDS_PROMPT_DANGEROUS_DOWNLOAD,
                                           elided_filename);
       }
-
     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_CONTENT:
     case content::DOWNLOAD_DANGER_TYPE_DANGEROUS_HOST:
-      return l10n_util::GetStringFUTF16(IDS_PROMPT_MALICIOUS_DOWNLOAD_CONTENT,
-                                        elided_filename);
-
+      if (trial_condition.empty()) {
+        return l10n_util::GetStringFUTF16(IDS_PROMPT_MALICIOUS_DOWNLOAD_CONTENT,
+                                          elided_filename);
+      } else {

[Dan Beam, 2013/08/10 00:13:56]

and here

[felt, 2013/08/10 00:33:00]

Done.

+        return download_util::AssembleMalwareFinchString(trial_condition,
+                                                         elided_filename);
+      }
     case content::DOWNLOAD_DANGER_TYPE_UNCOMMON_CONTENT:
       return l10n_util::GetStringFUTF16(IDS_PROMPT_UNCOMMON_DOWNLOAD_CONTENT,
                                         elided_filename);