No need for implbase1.hxx to include XComponentContext.hpp

...which it did unlike all the other implbaseN.hxx.  Required lots of downstream clean-up,
of course.

Change-Id: Ib720e7a0a43410dcd7e6338b84a3973dfbb20866

xmlsecurity/source/framework/encryptionengine.hxx

@@ -32,6 +32,10 @@
 
 #include "securityengine.hxx"
 
+namespace com { namespace sun { namespace star { namespace uno {
+    class XComponentContext;
+} } } }
+
 class EncryptionEngine : public cppu::ImplInheritanceHelper1
 <
     SecurityEngine,