Be more permissive of text failures

Now, the ignoreTextStreamFailures config applies to parsing errors as
well as network errors.

We also no longer count text streams against the startup phase.  Early
text failures will not prevent StreamingEngine from switching, without
regard for the presence of the ignoreTextStreamFailures config.

Issue #635

Change-Id: I6818ef021beabfbc8742a7b013fa0424b77cff47

lib/media/streaming_engine.js

@@ -1142,7 +1142,13 @@ shaka.media.StreamingEngine.prototype.fetchAndAppend_ = function(
       this.handleQuotaExceeded_(mediaState, error);
     } else {
       shaka.log.error(logPrefix, 'failed fetch and append: code=' + error.code);
-      this.onError_(error);
+      if (mediaState.type == 'text' && this.config_.ignoreTextStreamFailures) {
+        shaka.log.warning(logPrefix,
+            'Text stream failed to parse. Proceeding without it.');
+        delete this.mediaStates_['text'];
+      } else {
+        this.onError_(error);
+      }
     }
   }.bind(this));
 };
@@ -1160,7 +1166,8 @@ shaka.media.StreamingEngine.prototype.handleNetworkError_ = function(
   var logPrefix = shaka.media.StreamingEngine.logPrefix_(mediaState);
   if (mediaState.type == 'text' && this.config_.ignoreTextStreamFailures &&
       error.code == shaka.util.Error.Code.BAD_HTTP_STATUS) {
-    shaka.log.warning(logPrefix, 'Text stream failed. Proceeding without it.');
+    shaka.log.warning(logPrefix,
+        'Text stream failed to download. Proceeding without it.');
     delete this.mediaStates_['text'];
   } else {
     this.onError_(error);
@@ -1404,7 +1411,8 @@ shaka.media.StreamingEngine.prototype.handleStartup_ = function(
   var mediaStates = MapUtils.values(this.mediaStates_);
   this.startupComplete_ = mediaStates.every(function(ms) {
     // Startup completes once we have buffered at least one segment from each
-    // MediaState.
+    // MediaState, not counting text.
+    if (ms.type == 'text') return true;
     return !ms.waitingToClearBuffer &&
            !ms.clearingBuffer &&
            ms.lastSegmentReference;