fix(material/progress-bar): Support ChromeVox

Author: jamOne-

src/material/progress-bar/progress-bar.html

@@ -2,14 +2,14 @@
   The background div is named as such because it appears below the other divs and is not sized based
   on values.
 -->
-<svg width="100%" height="4" focusable="false" class="mat-progress-bar-background mat-progress-bar-element">
+<svg width="100%" height="4" focusable="false" class="mat-progress-bar-background mat-progress-bar-element" aria-hidden="true">
   <defs>
     <pattern [id]="progressbarId" x="4" y="0" width="8" height="4" patternUnits="userSpaceOnUse">
       <circle cx="2" cy="2" r="2"/>
     </pattern>
   </defs>
   <rect [attr.fill]="_rectangleFillValue" width="100%" height="100%"/>
 </svg>
-<div class="mat-progress-bar-buffer mat-progress-bar-element" [ngStyle]="_bufferTransform()"></div>
-<div class="mat-progress-bar-primary mat-progress-bar-fill mat-progress-bar-element" [ngStyle]="_primaryTransform()" #primaryValueBar></div>
-<div class="mat-progress-bar-secondary mat-progress-bar-fill mat-progress-bar-element"></div>
+<div class="mat-progress-bar-buffer mat-progress-bar-element" [ngStyle]="_bufferTransform()" aria-hidden="true"></div>
+<div class="mat-progress-bar-primary mat-progress-bar-fill mat-progress-bar-element" [ngStyle]="_primaryTransform()" #primaryValueBar aria-hidden="true"></div>
+<div class="mat-progress-bar-secondary mat-progress-bar-fill mat-progress-bar-element" aria-hidden="true"></div>