Bug 1054334 - Constify xpconnect's gNoString r=nbp

js/xpconnect/src/XPCJSID.cpp

@@ -21,10 +21,12 @@ using namespace JS;
 NS_IMPL_CLASSINFO(nsJSID, nullptr, 0, NS_JS_ID_CID)
 NS_IMPL_ISUPPORTS_CI(nsJSID, nsIJSID)
 
-char nsJSID::gNoString[] = "";
+const char nsJSID::gNoString[] = "";
 
 nsJSID::nsJSID()
-    : mID(GetInvalidIID()), mNumber(gNoString), mName(gNoString)
+    : mID(GetInvalidIID()),
+      mNumber(const_cast<char *>(gNoString)),
+      mName(const_cast<char *>(gNoString))
 {
 }
 
@@ -78,7 +80,7 @@ nsJSID::GetNumber(char * *aNumber)
 
     if (!mNumber) {
         if (!(mNumber = mID.ToString()))
-            mNumber = gNoString;
+            mNumber = const_cast<char *>(gNoString);
     }
 
     *aNumber = NS_strdup(mNumber);

js/xpconnect/src/xpcprivate.h

@@ -2743,7 +2743,7 @@ public:
     bool InitWithName(const nsID& id, const char *nameString);
     bool SetName(const char* name);
     void   SetNameToNoString()
-        {MOZ_ASSERT(!mName, "name already set"); mName = gNoString;}
+        {MOZ_ASSERT(!mName, "name already set"); mName = const_cast<char *>(gNoString);}
     bool NameIsSet() const {return nullptr != mName;}
     const nsID& ID() const {return mID;}
     bool IsValid() const {return !mID.Equals(GetInvalidIID());}
@@ -2758,7 +2758,7 @@ public:
 
 protected:
     virtual ~nsJSID();
-    static char gNoString[];
+    static const char gNoString[];
     nsID    mID;
     char*   mNumber;
     char*   mName;