Made all other "operator bool"s explicit and ensured

that all clients use them explicitly.  This will hopefully
prevent any future confusion where things get cast to types
we don't expect.

<rdar://problem/15146458>

llvm-svn: 191984

lldb/source/API/SBFileSpec.cpp

@@ -61,7 +61,7 @@ SBFileSpec::operator = (const SBFileSpec &rhs)
 bool
 SBFileSpec::IsValid() const
 {
-    return *m_opaque_ap;
+    return m_opaque_ap->operator bool();
 }
 
 bool