Fix implicit string-to-number conversions

This was caught by a compiler upgrade.

Issue shaka-project#2528

Change-Id: Ica262703aa30dce2e59c139c88f3c1e74d5d9e2f

lib/text/ttml_text_parser.js

@@ -613,7 +613,7 @@ shaka.text.TtmlTextParser = class {
     const opacity = TtmlTextParser.getStyleAttribute_(
         cueElement, region, styles, 'opacity');
     if (opacity) {
-      cue.opacity = opacity;
+      cue.opacity = parseFloat(opacity);
     }
 
     // Text decoration is an array of values which can come both from the

ui/range_element.js

@@ -147,16 +147,17 @@ shaka.ui.RangeElement = class extends shaka.ui.Element {
 
     const changedTouch = /** @type {TouchEvent} */ (event).changedTouches[0];
     const rect = this.bar.getBoundingClientRect();
+    const min = parseFloat(this.bar.min);
+    const max = parseFloat(this.bar.max);
 
     // Calculate the range value based on the touch position.
-    let value = (this.bar.max / rect.width) *
-      (changedTouch.clientX - rect.left);
+    let value = (max / rect.width) * (changedTouch.clientX - rect.left);
 
     // Keep value within bounds.
-    if (value < this.bar.min) {
-      value = this.bar.min;
-    } else if (value > this.bar.max) {
-      value = this.bar.max;
+    if (value < min) {
+      value = min;
+    } else if (value > max) {
+      value = max;
     }
 
     this.bar.value = value;