Cleanups in libjingle to make it compile with chromium_code=1

Fixed all warnings that show up when compiling libjingle
in chromium with compiling with chromium_code=1.
chromium_code=1 enables various warnings that are off by
default. Most changes are for unused variables and consts.

R=pthatcher@google.com, wu@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/9699004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5769 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/xmllite/xmlparser.cc b/talk/xmllite/xmlparser.cc
index 3e4d733..8802231 100644
--- a/talk/xmllite/xmlparser.cc
+++ b/talk/xmllite/xmlparser.cc
@@ -60,7 +60,7 @@
 }
 
 XmlParser::XmlParser(XmlParseHandler *pxph) :
-    context_(this), pxph_(pxph), sentError_(false) {
+    pxph_(pxph), sentError_(false) {
   expat_ = XML_ParserCreate(NULL);
   XML_SetUserData(expat_, this);
   XML_SetElementHandler(expat_, StartElementCallback, EndElementCallback);
@@ -196,8 +196,7 @@
   parser.Parse(text.c_str(), text.length(), true);
 }
 
-XmlParser::ParseContext::ParseContext(XmlParser *parser) :
-    parser_(parser),
+XmlParser::ParseContext::ParseContext() :
     xmlnsstack_(),
     raised_(XML_ERROR_NONE),
     line_number_(0),