Remove legacy drawing functions.
Skip element names starting with '#'

Change-Id: I6b0967ed1dc47c072c3bed7c0219e2215a7068a6
diff --git a/rsProgramVertex.cpp b/rsProgramVertex.cpp
index d667c86..e7292c0 100644
--- a/rsProgramVertex.cpp
+++ b/rsProgramVertex.cpp
@@ -160,6 +160,11 @@
             const Element *e = mInputElements[ct].get();
             for (uint32_t field=0; field < e->getFieldCount(); field++) {
                 const Element *f = e->getField(field);
+                const char *fn = e->getFieldName(field);
+
+                if (fn[0] == '#') {
+                    continue;
+                }
 
                 // Cannot be complex
                 rsAssert(!f->getFieldCount());
@@ -172,7 +177,7 @@
                     rsAssert(0);
                 }
 
-                mShader.append(e->getFieldName(field));
+                mShader.append(fn);
                 mShader.append(";\n");
             }
         }