Set up Finch trial for malware download warnings

chrome/browser/download/download_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Download utility implementation
 
 #include "chrome/browser/download/download_util.h"
 
 #include <cmath>
 #include <string>
@@ skipping 251 matching lines @@
 void RecordDownloadCount(ChromeDownloadCountTypes type) {
   UMA_HISTOGRAM_ENUMERATION(
       "Download.CountsChrome", type, CHROME_DOWNLOAD_COUNT_TYPES_LAST_ENTRY);
 }
 
 void RecordDownloadSource(ChromeDownloadSource source) {
   UMA_HISTOGRAM_ENUMERATION(
       "Download.SourcesChrome", source, CHROME_DOWNLOAD_SOURCE_LAST_ENTRY);
 }
 
+// Finch trial -----------------------------------------------------------------
+
+const char kFinchTrialName[] = "MalwareDownloadWarning";
+const char kCondition1Control[] = "Condition1Control";
+const char kCondition2Control[] = "Condition2Control";
+const char kCondition3Malicious[] = "Condition3Malicious";
+const char kCondition4Unsafe[] = "Condition4Unsafe";
+const char kCondition5Dangerous[] = "Condition5Dangerous";
+const char kCondition6Harmful[] = "Condition6Harmful";
+const char kCondition7DiscardSecond[] = "Condition7DiscardSecond";
+const char kCondition8DiscardFirst[] = "Condition8DiscardFirst";
+const char kCondition9SafeDiscard[] = "Condition9SafeDiscard";
+const char kCondition10SafeDontRun[] = "Condition10SafeDontRun";
+
+string16 AssembleMalwareFinchString(const std::string& trial_condition,

[Dan Beam, 2013/08/09 21:25:02]

base::string16 everywhere

[felt, 2013/08/09 22:38:03]

Done.

+                                    const string16& elided_filename) {
+  // Sanity check to make sure we have a filename.
+  string16 filename;
+  if (elided_filename.empty()) {

[Dan Beam, 2013/08/09 21:25:02]

nit: no curlies when if () and {} are 1-liners

[felt, 2013/08/09 22:38:03]

Is that in the style guide? I can't find it and it seems different reviewers
have different opinions about this.

(Done, though.)

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

"In general, curly braces are not required for single-line statements, but they
are allowed if you like them; conditional or loop statements with complex
conditions or statements may be more readable with curly braces."

http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml?showone=Condit...

In chrome we pretty much always omit *conditional* (if/else) curlies when
possible.  Some apply this rule to for/while etc., which is less consistent in
chrome and more disputed.

+    filename = ASCIIToUTF16("This file");
+  } else {
+    filename = elided_filename;
+  }

[Dan Beam, 2013/08/09 21:25:02]

nit: \n

[felt, 2013/08/09 22:38:03]

Done.

+  // Set the message text according to the condition.
+  string16 message_text;
+  if (trial_condition == kCondition1Control) {
+    message_text = ASCIIToUTF16("This file appears malicious.");
+  } else if (trial_condition == kCondition2Control) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' appears malicious."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition3Malicious) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is malicious."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition4Unsafe) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is unsafe."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition5Dangerous) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is dangerous."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition6Harmful) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is harmful."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition7DiscardSecond) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is malicious. Discard this file to stay safe."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition8DiscardFirst) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("Discard this file to stay safe. File '$1' is malicious."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition9SafeDiscard) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is malicious. To stay safe, discard it."),
+        filename,
+        NULL);
+  } else if (trial_condition == kCondition10SafeDontRun) {
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' is malicious. To stay safe, don't run it."),
+        filename,
+        NULL);
+  } else {
+    // We use the second control as a default for other conditions that don't
+    // change the warning string.
+    message_text = ReplaceStringPlaceholders(
+        ASCIIToUTF16("File '$1' appears malicious."),
+        filename,
+        NULL);
+  }

[Dan Beam, 2013/08/09 21:25:02]

nit: \n

[felt, 2013/08/09 22:38:03]

Done.

+  return message_text;
+}
+
 }  // namespace download_util