Fix slider step

Use the value of the `step` attribute if no keyboard steps are specified.

(cherry picked from commit 7d27596d6b)

src/elements/emby-slider/emby-slider.js

@@ -19,6 +19,27 @@ if (Object.getOwnPropertyDescriptor && Object.defineProperty) {
     }
 }
 
+/**
+ * Returns normalized slider step.
+ *
+ * @param {HTMLInputElement} range slider itself
+ * @param {number|undefined} step step
+ * @returns {number} normalized slider step.
+ */
+function normalizeSliderStep(range, step) {
+    if (step > 0) {
+        return step;
+    }
+
+    step = parseFloat(range.step);
+
+    if (step > 0) {
+        return step;
+    }
+
+    return 1;
+}
+
 /**
      * Returns slider fraction corresponding to client position.
      *
@@ -37,7 +58,7 @@ function mapClientToFraction(range, clientX) {
     // Snap to step
     const valueRange = range.max - range.min;
     if (range.step !== 'any' && valueRange !== 0) {
-        const step = (range.step || 1) / valueRange;
+        const step = normalizeSliderStep(range) / valueRange;
         fraction = Math.round(fraction / step) * step;
     }
 
@@ -56,7 +77,7 @@ function mapFractionToValue(range, fraction) {
 
     // Snap to step
     if (range.step !== 'any') {
-        const step = range.step || 1;
+        const step = normalizeSliderStep(range);
         value = Math.round(value / step) * step;
     }
 
@@ -455,13 +476,13 @@ function onKeyDown(e) {
     switch (keyboardnavigation.getKeyName(e)) {
         case 'ArrowLeft':
         case 'Left':
-            stepKeyboard(this, -this.keyboardStepDown || -1);
+            stepKeyboard(this, -normalizeSliderStep(this, this.keyboardStepDown));
             e.preventDefault();
             e.stopPropagation();
             break;
         case 'ArrowRight':
         case 'Right':
-            stepKeyboard(this, this.keyboardStepUp || 1);
+            stepKeyboard(this, normalizeSliderStep(this, this.keyboardStepUp));
             e.preventDefault();
             e.stopPropagation();
             break;