fix(HLS): Fix url management in HLS (shaka-project#5722)

Fix variable substitution in: AES-128 key and EXT-X-SESSION-DATA urls.
Fix to keep previous query params when using blocking playlist reload
Simplifies and unifies URL management to allow Content Steering in the
future

Backported to v4.4.x

lib/hls/hls_classes.js

@@ -11,7 +11,6 @@ goog.provide('shaka.hls.Segment');
 goog.provide('shaka.hls.Tag');
 
 goog.require('goog.asserts');
-goog.require('shaka.hls.Utils');
 goog.require('shaka.util.Error');
 
 
@@ -203,48 +202,20 @@ shaka.hls.Segment = class {
   /**
    * Creates an HLS segment object.
    *
-   * @param {string} absoluteMediaPlaylistUri An absolute Media Playlist URI.
    * @param {string} verbatimSegmentUri verbatim segment URI.
    * @param {!Array.<shaka.hls.Tag>} tags
    * @param {!Array.<shaka.hls.Tag>=} partialSegments
    */
-  constructor(absoluteMediaPlaylistUri, verbatimSegmentUri, tags,
-      partialSegments=[]) {
+  constructor(verbatimSegmentUri, tags, partialSegments=[]) {
     /** @const {!Array.<shaka.hls.Tag>} */
     this.tags = tags;
 
-    /** @type {?string} */
-    this.absoluteUri_ = null;
-
-    /** @type {?string} */
-    this.absoluteMediaPlaylistUri_ = absoluteMediaPlaylistUri;
-
-    /** @type {?string} */
-    this.verbatimSegmentUri_ = verbatimSegmentUri;
+    /** @const {?string} */
+    this.verbatimSegmentUri = verbatimSegmentUri;
 
     /** @type {!Array.<shaka.hls.Tag>} */
     this.partialSegments = partialSegments;
   }
-
-  /**
-   * Returns an absolute URI.
-   *
-   * @return {string}
-   */
-  get absoluteUri() {
-    if (!this.absoluteUri_ &&
-        this.absoluteMediaPlaylistUri_ && this.verbatimSegmentUri_) {
-      goog.asserts.assert(this.absoluteMediaPlaylistUri_,
-          'An absolute Media Playlist URI should be defined!');
-      goog.asserts.assert(this.verbatimSegmentUri_,
-          'An verbatim segment URI should be defined!');
-      this.absoluteUri_ = shaka.hls.Utils.constructAbsoluteUri(
-          this.absoluteMediaPlaylistUri_, this.verbatimSegmentUri_);
-      this.absoluteMediaPlaylistUri_ = null;
-      this.verbatimSegmentUri_ = null;
-    }
-    return this.absoluteUri_ || '';
-  }
 };