Revert "🐛 Bug fix: Permissions Policy syntax for sync-xhr to eliminate console violations (#40378)" (#40380)

This reverts commit 8bb4ac0.

Author: danielrozenberg

extensions/amp-a4a/0.1/amp-a4a.js

@@ -2071,13 +2071,13 @@ export class AmpA4A extends AMP.BaseElement {
     // Block synchronous XHR in ad. These are very rare, but super bad for UX
     // as they block the UI thread for the arbitrary amount of time until the
     // request completes.
-    let permissionPolicies = 'sync-xhr=()';
+    let featurePolicies = "sync-xhr 'none';";
 
     if (isAttributionReportingAllowed(this.win.document)) {
-      permissionPolicies += ";attribution-reporting 'src';";
+      featurePolicies += "attribution-reporting 'src';";
     }
 
-    mergedAttributes['allow'] = permissionPolicies;
+    mergedAttributes['allow'] = featurePolicies;
 
     this.maybeDestroyIframe_();
     this.iframe = /** @type {!HTMLIFrameElement} */ (

extensions/amp-a4a/0.1/test/test-amp-a4a.js

@@ -918,7 +918,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
         a4a.onLayoutMeasure();
         await a4a.layoutCallback();
         verifyCachedContentIframeRender(a4aElement, TEST_URL, true);
-        expect(a4a.iframe.getAttribute('allow')).to.include('sync-xhr=();');
+        expect(a4a.iframe.getAttribute('allow')).to.include("sync-xhr 'none';");
       });
 
       it('should set feature policy for attribution-reporting when supported', async () => {
@@ -929,7 +929,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
         a4a.onLayoutMeasure();
         await a4a.layoutCallback();
         verifyCachedContentIframeRender(a4aElement, TEST_URL, true);
-        expect(a4a.iframe.getAttribute('allow')).to.include('sync-xhr=();');
+        expect(a4a.iframe.getAttribute('allow')).to.include("sync-xhr 'none';");
         expect(a4a.iframe.getAttribute('allow')).to.include(
           "attribution-reporting 'src';"
         );
@@ -943,7 +943,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
         a4a.onLayoutMeasure();
         await a4a.layoutCallback();
         verifyCachedContentIframeRender(a4aElement, TEST_URL, true);
-        expect(a4a.iframe.getAttribute('allow')).to.include('sync-xhr=()');
+        expect(a4a.iframe.getAttribute('allow')).to.include("sync-xhr 'none';");
         expect(a4a.iframe.getAttribute('allow')).to.not.include(
           "attribution-reporting 'src';"
         );
@@ -1046,7 +1046,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
         await a4a.layoutCallback();
         verifyNameFrameRender(a4aElement, false /* shouldSandbox */);
         expect(a4a.iframe.getAttribute('allow')).to.equal(
-          "sync-xhr=();attribution-reporting 'src';"
+          "sync-xhr 'none';attribution-reporting 'src';"
         );
       });
 
@@ -1058,7 +1058,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
         a4a.onLayoutMeasure();
         await a4a.layoutCallback();
         verifyNameFrameRender(a4aElement, false /* shouldSandbox */);
-        expect(a4a.iframe.getAttribute('allow')).to.equal('sync-xhr=()');
+        expect(a4a.iframe.getAttribute('allow')).to.equal("sync-xhr 'none';");
       });
 
       ['', 'client_cache', 'safeframe', 'some_random_thing'].forEach(
@@ -1183,7 +1183,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
           false /* shouldSandbox */
         );
         expect(a4a.iframe.getAttribute('allow')).to.equal(
-          "sync-xhr=();attribution-reporting 'src';"
+          "sync-xhr 'none';attribution-reporting 'src';"
         );
       });
 
@@ -1199,7 +1199,7 @@ describes.realWin('amp-a4a', {amp: true}, (env) => {
           DEFAULT_SAFEFRAME_VERSION,
           false /* shouldSandbox */
         );
-        expect(a4a.iframe.getAttribute('allow')).to.equal('sync-xhr=()');
+        expect(a4a.iframe.getAttribute('allow')).to.equal("sync-xhr 'none';");
       });
 
       ['', 'client_cache', 'nameframe', 'some_random_thing'].forEach(

src/3p-frame.js

@@ -132,7 +132,7 @@ export function getIframe(
   // Block synchronous XHR in ad. These are very rare, but super bad for UX
   // as they block the UI thread for the arbitrary amount of time until the
   // request completes.
-  iframe.setAttribute('allow', 'sync-xhr=();');
+  iframe.setAttribute('allow', "sync-xhr 'none';");
   const excludeFromSandbox = ['facebook'];
   if (!excludeFromSandbox.includes(opt_type)) {
     applySandbox(iframe);

src/preact/component/3p-frame.js

@@ -28,7 +28,7 @@ export const countGenerators = {};
 // Block synchronous XHR in ad. These are very rare, but super bad for UX
 // as they block the UI thread for the arbitrary amount of time until the
 // request completes.
-const BLOCK_SYNC_XHR = 'sync-xhr=()';
+const BLOCK_SYNC_XHR = "sync-xhr 'none'";
 
 // TODO(wg-bento): UA check for required flags without iframe element
 const DEFAULT_SANDBOX =

test/unit/3p/test-3p-frame.js

@@ -263,7 +263,7 @@ describes.realWin('3p-frame', {amp: true}, (env) => {
         setupElementFunctions(div);
         container.appendChild(div);
         const iframe = getIframe(window, div, 'none');
-        expect(iframe.getAttribute('allow')).to.equal('sync-xhr=();');
+        expect(iframe.getAttribute('allow')).to.equal("sync-xhr 'none';");
       });
 
       it('should set sandbox', () => {