fix: restore svg image DataURL dimensions (#8730)

packages/excalidraw/data/blob.ts

@@ -8,13 +8,14 @@ import { calculateScrollCenter } from "../scene";
 import type { AppState, DataURL, LibraryItem } from "../types";
 import type { ValueOf } from "../utility-types";
 import { bytesToHexString, isPromiseLike } from "../utils";
+import { base64ToString, stringToBase64, toByteString } from "./encode";
 import type { FileSystemHandle } from "./filesystem";
 import { nativeFileSystemSupported } from "./filesystem";
 import { isValidExcalidrawData, isValidLibrary } from "./json";
 import { restore, restoreLibraryItems } from "./restore";
 import type { ImportedLibraryData } from "./types";
 
-const parseFileContents = async (blob: Blob | File) => {
+const parseFileContents = async (blob: Blob | File): Promise<string> => {
   let contents: string;
 
   if (blob.type === MIME_TYPES.png) {
@@ -46,9 +47,7 @@ const parseFileContents = async (blob: Blob | File) => {
     }
     if (blob.type === MIME_TYPES.svg) {
       try {
-        return await (
-          await import("./image")
-        ).decodeSvgMetadata({
+        return (await import("./image")).decodeSvgMetadata({
           svg: contents,
         });
       } catch (error: any) {
@@ -249,6 +248,7 @@ export const generateIdFromFile = async (file: File): Promise<FileId> => {
   }
 };
 
+/** async. For sync variant, use getDataURL_sync */
 export const getDataURL = async (file: Blob | File): Promise<DataURL> => {
   return new Promise((resolve, reject) => {
     const reader = new FileReader();
@@ -261,6 +261,16 @@ export const getDataURL = async (file: Blob | File): Promise<DataURL> => {
   });
 };
 
+export const getDataURL_sync = (
+  data: string | Uint8Array | ArrayBuffer,
+  mimeType: ValueOf<typeof MIME_TYPES>,
+): DataURL => {
+  return `data:${mimeType};base64,${stringToBase64(
+    toByteString(data),
+    true,
+  )}` as DataURL;
+};
+
 export const dataURLToFile = (dataURL: DataURL, filename = "") => {
   const dataIndexStart = dataURL.indexOf(",");
   const byteString = atob(dataURL.slice(dataIndexStart + 1));
@@ -274,6 +284,10 @@ export const dataURLToFile = (dataURL: DataURL, filename = "") => {
   return new File([ab], filename, { type: mimeType });
 };
 
+export const dataURLToString = (dataURL: DataURL) => {
+  return base64ToString(dataURL.slice(dataURL.indexOf(",") + 1));
+};
+
 export const resizeImageFile = async (
   file: File,
   opts: {