Remove safe_browsing=2 functionality, replace with =3 mode.

Remove refs to SAFE_BROWSING_SERVICE, MOBILE_SAFE_BROWSING,
and removes the half-dead code that supported
FULL_SAFE_BROWSING on Android.

This affects no change in functionality.

BUG=542795

Review URL: https://codereview.chromium.org/1402783005

Cr-Commit-Position: refs/heads/master@{#354535}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 08593186..5d0b829 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -505,11 +505,11 @@
       if (is_win) {
         deps += [ "//chrome/browser/safe_browsing/incident_reporting:state_store_data_proto" ]
       }
-    } else if (safe_browsing_mode == 3) {
-      sources += rebase_path(
-              gypi_values.chrome_browser_safe_browsing_mobile_extended_sources,
-              ".",
-              "//chrome")
+    } else if (safe_browsing_mode == 2) {
+      sources +=
+          rebase_path(gypi_values.chrome_browser_safe_browsing_mobile_sources,
+                      ".",
+                      "//chrome")
     }
   }