fix(DASH): decrease memory preasure on manifest with SegmentReference…

… by updating old initSegmentReference (#6499)

Helps on #6070

Backported to v4.7.x

AUTHORS

@@ -28,6 +28,7 @@ Bonnier Broadcasting <*@bonnierbroadcasting.com>
 Bryan Huh <bhh1988@gmail.com>
 Charter Communications Inc <*@charter.com>
 Code It <*@code-it.fr>
+Cristian Atehortua <cristian25a32@gmail.com>
 Damien Deis <developer.deis@gmail.com>
 Dany L'Hébreux <danylhebreux@gmail.com>
 Dave Nicholas <davenicholasuk@gmail.com>

CONTRIBUTORS

@@ -44,6 +44,7 @@ Casey Occhialini <casey.occhialini@gmail.com>
 Chad Assareh <assareh@google.com>
 Chris Fillmore <fillmore.chris@gmail.com>
 Costel Madalin Grecu <madalin.grecu@adswizz.com>
+Cristian Atehortua <cristian25a32@gmail.com>
 Damien Deis <developer.deis@gmail.com>
 Dany L'Hébreux <danylhebreux@gmail.com>
 Dave Nicholas <davenicholasuk@gmail.com>

lib/dash/segment_template.js

@@ -701,7 +701,7 @@ shaka.dash.TimelineSegmentIndex = class extends shaka.media.SegmentIndex {
    */
   appendTemplateInfo(info, periodStart, periodEnd, shouldFit,
       initSegmentReference) {
-    this.initSegmentReference_ = initSegmentReference;
+    this.updateInitSegmentReference(initSegmentReference);
     if (!this.templateInfo_) {
       this.templateInfo_ = info;
       this.periodStart_ = periodStart;
@@ -732,6 +732,24 @@ shaka.dash.TimelineSegmentIndex = class extends shaka.media.SegmentIndex {
     }
   }
 
+  /**
+   * Updates the init segment reference and propagates the update to all
+   * references.
+   * @param {shaka.media.InitSegmentReference} initSegmentReference
+   */
+  updateInitSegmentReference(initSegmentReference) {
+    if (this.initSegmentReference_ === initSegmentReference) {
+      return;
+    }
+
+    this.initSegmentReference_ = initSegmentReference;
+    for (const reference of this.references) {
+      if (reference) {
+        reference.updateInitSegmentReference(initSegmentReference);
+      }
+    }
+  }
+
   /**
    *
    * @param {number} time

lib/media/segment_reference.js

@@ -598,6 +598,18 @@ shaka.media.SegmentReference = class {
       this.offset(offset);
     }
   }
+
+  /**
+   * Updates the init segment reference and propagates the update to all partial
+   * references.
+   * @param {shaka.media.InitSegmentReference} initSegmentReference
+   */
+  updateInitSegmentReference(initSegmentReference) {
+    this.initSegmentReference = initSegmentReference;
+    for (const partialReference of this.partialReferences) {
+      partialReference.updateInitSegmentReference(initSegmentReference);
+    }
+  }
 };