Remove resized element if it is invisibly small (#405)

src/element/index.ts

@@ -12,3 +12,4 @@ export { resizeTest } from "./resizeTest";
 export { isTextElement } from "./typeChecks";
 export { textWysiwyg } from "./textWysiwyg";
 export { redrawTextBoundingBox } from "./textElement";
+export { isInvisiblySmallElement } from "./sizeChecks";

src/element/sizeChecks.ts

@@ -0,0 +1,5 @@
+import { ExcalidrawElement } from "./types";
+
+export function isInvisiblySmallElement(element: ExcalidrawElement): boolean {
+  return element.width === 0 && element.height === 0;
+}