Merge pull request #3911 from yurydelendik/mem-redux2

Cleaning up fonts when viewer is idle for some time

src/display/api.js

@@ -276,6 +276,9 @@ var PDFDocumentProxy = (function PDFDocumentProxyClosure() {
     dataLoaded: function PDFDocumentProxy_dataLoaded() {
       return this.transport.dataLoaded();
     },
+    cleanup: function PDFDocumentProxy_cleanup() {
+      this.transport.startCleanup();
+    },
     destroy: function PDFDocumentProxy_destroy() {
       this.transport.destroy();
     }
@@ -907,6 +910,21 @@ var WorkerTransport = (function WorkerTransportClosure() {
         }
       );
       return promise;
+    },
+
+    startCleanup: function WorkerTransport_startCleanup() {
+      this.messageHandler.send('Cleanup', null,
+        function endCleanup() {
+          for (var i = 0, ii = this.pageCache.length; i < ii; i++) {
+            var page = this.pageCache[i];
+            if (page) {
+              page.destroy();
+            }
+          }
+          this.commonObjs.clear();
+          FontLoader.clear();
+        }.bind(this)
+      );
     }
   };
   return WorkerTransport;

src/display/font_loader.js

@@ -33,6 +33,12 @@ var FontLoader = {
     var styleSheet = styleElement.sheet;
     styleSheet.insertRule(rule, styleSheet.cssRules.length);
   },
+  clear: function fontLoaderClear() {
+    var styleElement = document.getElementById('PDFJS_FONT_STYLE_TAG');
+    if (styleElement) {
+      styleElement.parentNode.removeChild(styleElement);
+    }
+  },
 //#if !(MOZCENTRAL)
   get loadTestFont() {
     // This is a CFF font with 1 glyph for '.' that fills its entire width and