Convert macros from plain QByteArray to a vector of structs

The old code model expected the macros as C++ formatted text
("#define Foo 42) but newer targets like the Clang codemodel expect key
value arguments like "-DFoo=42". So instead of parsing the text again and
again we use an abstract data description.

Task-number: QTCREATORBUG-17915
Change-Id: I0179fd13c48a581e91ee79bba9d42d501c26f19f
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

tests/unit/unittest/google-using-declarations.h

@@ -43,4 +43,5 @@ using testing::Property;
 using testing::Return;
 using testing::ReturnRef;
 using testing::Sequence;
+using testing::StrEq;
 using testing::UnorderedElementsAre;