feat: make desktopCapturer main-process-only (#30720)

* feat: make desktopCapturer main-process-only

* remove --enable-api-filtering-logging

* remove test

* merge lib/browser/api/desktop-capturer.ts with lib/browser/desktop-capturer.ts

* remove desktop-capturer-get-sources event

* fix specs

* getSources needs to be async

Co-authored-by: Milan Burda <milan.burda@gmail.com>

lib/browser/api/desktop-capturer.ts

@@ -1,5 +1,72 @@
-import { getSourcesImpl } from '@electron/internal/browser/desktop-capturer';
+const { createDesktopCapturer } = process._linkedBinding('electron_browser_desktop_capturer');
 
-export async function getSources (options: Electron.SourcesOptions) {
-  return getSourcesImpl(null, options);
+const deepEqual = (a: ElectronInternal.GetSourcesOptions, b: ElectronInternal.GetSourcesOptions) => JSON.stringify(a) === JSON.stringify(b);
+
+let currentlyRunning: {
+  options: ElectronInternal.GetSourcesOptions;
+  getSources: Promise<ElectronInternal.GetSourcesResult[]>;
+}[] = [];
+
+// |options.types| can't be empty and must be an array
+function isValid (options: Electron.SourcesOptions) {
+  const types = options ? options.types : undefined;
+  return Array.isArray(types);
+}
+
+export async function getSources (args: Electron.SourcesOptions) {
+  if (!isValid(args)) throw new Error('Invalid options');
+
+  const captureWindow = args.types.includes('window');
+  const captureScreen = args.types.includes('screen');
+
+  const { thumbnailSize = { width: 150, height: 150 } } = args;
+  const { fetchWindowIcons = false } = args;
+
+  const options = {
+    captureWindow,
+    captureScreen,
+    thumbnailSize,
+    fetchWindowIcons
+  };
+
+  for (const running of currentlyRunning) {
+    if (deepEqual(running.options, options)) {
+      // If a request is currently running for the same options
+      // return that promise
+      return running.getSources;
+    }
+  }
+
+  const getSources = new Promise<ElectronInternal.GetSourcesResult[]>((resolve, reject) => {
+    let capturer: ElectronInternal.DesktopCapturer | null = createDesktopCapturer();
+
+    const stopRunning = () => {
+      if (capturer) {
+        delete capturer._onerror;
+        delete capturer._onfinished;
+        capturer = null;
+      }
+      // Remove from currentlyRunning once we resolve or reject
+      currentlyRunning = currentlyRunning.filter(running => running.options !== options);
+    };
+
+    capturer._onerror = (error: string) => {
+      stopRunning();
+      reject(error);
+    };
+
+    capturer._onfinished = (sources: Electron.DesktopCapturerSource[]) => {
+      stopRunning();
+      resolve(sources);
+    };
+
+    capturer.startHandling(captureWindow, captureScreen, thumbnailSize, fetchWindowIcons);
+  });
+
+  currentlyRunning.push({
+    options,
+    getSources
+  });
+
+  return getSources;
 }