Fix const with newdecls and a varargs bug. (bug 6179)

sourcepawn/compiler/tests/ok-methodmap-semis.sp

@@ -1,5 +1,7 @@
 #pragma semicolon 1
 
+native IsValidEntity(entity);
+
 methodmap Entity
 {
 	public Entity(const char[] className) {

sourcepawn/compiler/tests/ok-newdecl-const.sp

@@ -0,0 +1,12 @@
+// both fine
+const MY_CONST = 1;
+const Float:FLOAT_CONST = 1.0;
+
+// error 020: invalid symbol name ""
+const int MY_INT_COST = 1;
+// error 001: expected token: "=", but found "-identifier-"
+const float MY_FLOAT_CONST = 1.0;
+
+public main()
+{
+}