Fixed another issue with declaring instance vars in initialize

spec/compiler/type_inference/class_spec.cr

@@ -709,4 +709,21 @@ describe "Type inference: class" do
       ),
       "type vars must be A, B, not C"
   end
+
+  it "allows declaring a variable in an initialize and using it" do
+    assert_type(%(
+      class Foo
+        def initialize
+          @x :: Int32
+          @x + 1
+        end
+
+        def x
+          @x
+        end
+      end
+
+      Foo.new.x
+      )) { int32 }
+  end
 end

src/compiler/crystal/type_inference.cr

@@ -238,7 +238,12 @@ module Crystal
           ivar = lookup_instance_var var
           ivar.bind_to node
           var.bind_to node
+
+          if @is_initialize
+            @vars[var.name] = MetaVar.new(var.name, node.type)
+          end
         end
+
         case type
         when NonGenericClassType
           node.declared_type.accept self