fix(platform-browser): Use the right namespace for mathML.

Prior to this change, MathML element were created with the wrong namespace resulting in regular DOM `Element`.

This commit fixes this.

Related to angular#55608 (but doesn't fix it entirely).

packages/platform-browser/src/dom/dom_renderer.ts

@@ -35,7 +35,7 @@ export const NAMESPACE_URIS: {[ns: string]: string} = {
   'xlink': 'http://www.w3.org/1999/xlink',
   'xml': 'http://www.w3.org/XML/1998/namespace',
   'xmlns': 'http://www.w3.org/2000/xmlns/',
-  'math': 'http://www.w3.org/1998/MathML/',
+  'math': 'http://www.w3.org/1998/Math/MathML',
 };
 
 const COMPONENT_REGEX = /%COMP%/g;

packages/platform-browser/test/dom/dom_renderer_spec.ts

@@ -252,6 +252,20 @@ describe('DefaultDomRendererV2', () => {
       expect(await styleCount(fixture, '.emulated')).toBe(0);
     });
   });
+
+  describe('should support namespaces', () => {
+    it('should create SVG elements', () => {
+      expect(
+        document.createElementNS(NAMESPACE_URIS['svg'], 'math') instanceof SVGElement,
+      ).toBeTrue();
+    });
+
+    it('should create MathML elements', () => {
+      expect(
+        document.createElementNS(NAMESPACE_URIS['math'], 'math') instanceof MathMLElement,
+      ).toBeTrue();
+    });
+  });
 });
 
 async function styleCount(