Set URL in history.replaceState/pushState

When <base href> is present, history.replaceState and
history.pushState behave inconsistent with relative URLs.
http://code.google.com/p/chromium/issues/detail?id=274024

Contrary to what one expect, passing '' as the URL parameter to
replaceState/pushState does not associate the currently active
URL with the history entry, but a path relative to <base href>.

To fix the issue, explicitly associate the current active URL
with the history's state.

web/pdf_history.js

@@ -65,7 +65,8 @@ var PDFHistory = {
         // is opened in the web viewer.
         this.reInitialized = true;
       }
-      window.history.replaceState({ fingerprint: this.fingerprint }, '');
+      window.history.replaceState({ fingerprint: this.fingerprint }, '',
+          document.URL);
     }
 
     var self = this;
@@ -270,9 +271,9 @@ var PDFHistory = {
       }
     }
     if (overwrite || this.uid === 0) {
-      window.history.replaceState(this._stateObj(params), '');
+      window.history.replaceState(this._stateObj(params), '', document.URL);
     } else {
-      window.history.pushState(this._stateObj(params), '');
+      window.history.pushState(this._stateObj(params), '', document.URL);
     }
     this.currentUid = this.uid++;
     this.current = params;