fix(progress-bar): buffer animation not working in IE

Fixes an issue that caused IE to throw an XML error and not render the buffering animation. The problem was that we url-escape the SVG itself, but not the hex color which gets added later on, which causes the url to be invalid. This seems to be handled by most browsers automatically, but not IE.

Fixes angular#2881.

src/lib/progress-bar/_progress-bar-theme.scss

@@ -48,23 +48,31 @@
 
 // TODO(josephperrott): Find better way to inline svgs.
 // In buffer mode a repeated SVG object is used as a background.
-//  Each of the following defines the SVG object for each of the class defined colors.
+// Each of the following defines the SVG object for each of the class defined colors.
 //
-//  The string is a URL encoded version of:
+// The string is a URL encoded version of:
 //
-//  <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
-//       version="1.1" x="0px" y="0px" enable-background="new 0 0 5 2"
-//       xml:space="preserve" viewBox="0 0 5 2" preserveAspectRatio="none slice">
-//    <circle cx="1" cy="1" r="1" fill="{INJECTED_COLOR}"/>
-//  </svg>
+// <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
+//      version="1.1" x="0px" y="0px" enable-background="new 0 0 5 2"
+//      xml:space="preserve" viewBox="0 0 5 2" preserveAspectRatio="none slice">
+//   <circle cx="1" cy="1" r="1" fill="{INJECTED_COLOR}"/>
+// </svg>
 @function _mat-progress-bar-buffer($palette, $hue) {
- $result: '' +
-   'data:image/svg+xml;charset=UTF-8,%3Csvg%20version%3D%271.1%27%20xmlns%3D%27http%3A%2F%2F' +
-   'www.w3.org%2F2000%2Fsvg%27%20xmlns%3Axlink%3D%27http%3A%2F%2Fwww.w3.org%2F1999%2Fxlink%2' +
-   '7%20x%3D%270px%27%20y%3D%270px%27%20enable-background%3D%27new%200%200%205%202%27%20xml%' +
-   '3Aspace%3D%27preserve%27%20viewBox%3D%270%200%205%202%27%20preserveAspectRatio%3D%27none' +
-   '%20slice%27%3E%3Ccircle%20cx%3D%271%27%20cy%3D%271%27%20r%3D%271%27%20fill%3D%27' +
-    mat-color($palette, $hue) + '%27%2F%3E%3C%2Fsvg%3E';
+  $color: md-color($palette, $hue) + '';
+
+  // We also need to escape the hash in hex colors,
+  // otherwise IE will throw an XML error.
+  @if str-index($color, "#") == 1 {
+    $color: '%23' + str-slice($color, 2);
+  }
+
+  $result: '' +
+    'data:image/svg+xml;charset=UTF-8,%3Csvg%20version%3D%271.1%27%20xmlns%3D%27http%3A%2F%2F' +
+    'www.w3.org%2F2000%2Fsvg%27%20xmlns%3Axlink%3D%27http%3A%2F%2Fwww.w3.org%2F1999%2Fxlink%2' +
+    '7%20x%3D%270px%27%20y%3D%270px%27%20enable-background%3D%27new%200%200%205%202%27%20xml%' +
+    '3Aspace%3D%27preserve%27%20viewBox%3D%270%200%205%202%27%20preserveAspectRatio%3D%27none' +
+    '%20slice%27%3E%3Ccircle%20cx%3D%271%27%20cy%3D%271%27%20r%3D%271%27%20fill%3D%27' +
+    $color + '%27%2F%3E%3C%2Fsvg%3E';
 
   @return url($result);
 }