Surfaceflinger: Document DdmConnection usage

Change-Id: Iebb1448ea8421b6bc8e5aedff64dddc50dbb012a
diff --git a/services/surfaceflinger/DdmConnection.h b/services/surfaceflinger/DdmConnection.h
index b6b088b..938d14b 100644
--- a/services/surfaceflinger/DdmConnection.h
+++ b/services/surfaceflinger/DdmConnection.h
@@ -24,6 +24,9 @@
 
 class DdmConnection {
 public:
+    // Creates a JVM and registers all handlers to DDMS.
+    // This allows tools relying on DDMS to find surfaceflinger
+    // (e.g: Memory Leak finder, heap analyzer, ...)
     static void start(const char* name);
 };