Keep two empty lines between declarations for cpp files

samples/process.cc

Index: samples/process.cc
===================================================================
--- samples/process.cc	(revision 15486)
+++ samples/process.cc	(working copy)
@@ -54,6 +54,7 @@
   virtual const string& UserAgent() = 0;
 };
 
+
 /**
  * The abstract superclass of http request processors.
  */
@@ -72,6 +73,7 @@
   static void Log(const char* event);
 };
 
+
 /**
  * An http request processor that is scriptable using JavaScript.
  */
@@ -135,6 +137,7 @@
   static Persistent<ObjectTemplate> map_template_;
 };
 
+
 // -------------------------
 // --- P r o c e s s o r ---
 // -------------------------