Add the BUILD files for content_resources.

content/app/resources/content_resources.grd

Index: content/app/resources/content_resources.grd
diff --git a/webkit/glue/resources/webkit_resources.grd b/content/app/resources/content_resources.grd
similarity index 97%
copy from webkit/glue/resources/webkit_resources.grd
copy to content/app/resources/content_resources.grd
index 42654c5e9535d9846defa07e1dfe8b0ae8a9ab33..00685395dbdcf13166a1a2fb03b47bf9e9653ec7 100644
--- a/webkit/glue/resources/webkit_resources.grd
+++ b/content/app/resources/content_resources.grd
@@ -1,11 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <grit latest_public_release="0" current_release="1">
   <outputs>
-    <output filename="grit/webkit_resources.h" type="rc_header" context="default_100_percent">
+    <output filename="grit/content_resources.h" type="rc_header" context="default_100_percent">
       <emit emit_type='prepend'></emit>
     </output>
-    <output filename="webkit_resources_100_percent.pak" type="data_package" context="default_100_percent" />
-    <output filename="webkit_resources_200_percent.pak" type="data_package" context="default_200_percent" />
+    <output filename="content_resources_100_percent.pak" type="data_package" context="default_100_percent" />
+    <output filename="content_resources_200_percent.pak" type="data_package" context="default_200_percent" />
   </outputs>
   <release seq="1">
     <structures fallback_to_low_resolution="true">