Add Simple Cache choice to about:flags

This is done with a multiple choice because later we will add another option:
"choose the cache backend at random", and make it the default.

BUG=173390,173381

Review URL: https://chromiumcodereview.appspot.com/13862014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193396 0039d316-1c4b-4281-b951-d872f2087c98

chrome/app/generated_resources.grd

@@ -14933,6 +14933,14 @@ Some features may be unavailable.  Please check that the profile exists and you
       Enable virtual keyboard support.
     </message>
 
+    <!-- Simple Cache Backend experiment. -->
+    <message name="IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_NAME" desc="Name of about:flags option to turn on the Simple Cache Backend">
+      Enable the Simple Cache for HTTP. Unstable! It may corrupt your cache! Do not use this option.
+    </message>
+    <message name="IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_DESCRIPTION" desc="Description of about:flags option to turn on the Simple Cache Backend">
+      The Simple Cache for HTTP is a new cache. It relies on the filesystem for disk space allocation.
+    </message>
+
     <!-- Toast experiment. -->
     <message name="IDS_TRY_TOAST_SET_DEFAULT" desc="Text of the checkbox to make chrome the default browser">
       Make it my default browser

chrome/browser/about_flags.cc

@@ -225,6 +225,12 @@ const Experiment::Choice kMaxTilesForInterestAreaChoices[] = {
     cc::switches::kMaxTilesForInterestArea, "512"}
 };
 
+const Experiment::Choice kSimpleCacheBackendChoices[] = {
+  { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED, "", "off" },
+  { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
+    switches::kUseSimpleCacheBackend, "on"}
+};
+
 // RECORDING USER METRICS FOR FLAGS:
 // -----------------------------------------------------------------------------
 // The first line of the experiment is the internal name. If you'd like to
@@ -1326,6 +1332,13 @@ const Experiment kExperiments[] = {
     SINGLE_VALUE_TYPE(keyboard::switches::kEnableVirtualKeyboard)
   },
 #endif
+  {
+    "enable-simple-cache-backend",
+    IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_NAME,
+    IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_DESCRIPTION,
+    kOsAndroid,
+    MULTI_VALUE_TYPE(kSimpleCacheBackendChoices)
+  },
 };
 
 const Experiment* experiments = kExperiments;