Get rid of dependencies on v8.h in public header files

src/JsError.h

Index: src/JsError.h
===================================================================
new file mode 100644
--- /dev/null
+++ b/src/JsError.h
@@ -0,0 +1,53 @@
+/*
+ * This file is part of Adblock Plus <http://adblockplus.org/>,
+ * Copyright (C) 2006-2013 Eyeo GmbH
+ *
+ * Adblock Plus is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * Adblock Plus is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Adblock Plus.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef ADBLOCK_PLUS_JS_ERROR_H
+#define ADBLOCK_PLUS_JS_ERROR_H
+
+#include <sstream>
+#include <stdexcept>
+#include <v8.h>
+
+namespace
+{
+  std::string ExceptionToString(const v8::Handle<v8::Value> exception,
+      const v8::Handle<v8::Message> message)
+  {
+    std::stringstream error;
+    error << *v8::String::Utf8Value(exception);
+    if (!message.IsEmpty())
+    {
+      error << " at ";
+      error << *v8::String::Utf8Value(message->GetScriptResourceName());
+      error << ":";
+      error << message->GetLineNumber();
+    }
+    return error.str();
+  }
+}
+
+namespace AdblockPlus
+{
+  class JsError : public std::runtime_error
+  {
+  public:
+    JsError(const v8::Handle<v8::Value> exception,
+            const v8::Handle<v8::Message> message);
+  };
+}
+
+#endif