[roottest] rename ABC -> BaseABC in tree/branches tests

ABC used in some Windows headers as type and conflict with ABC type name used in the original test

Author: linev

roottest/root/tree/branches/abc.h

@@ -1,27 +1,27 @@
-class ABC {
+class BaseABC {
 public:
-   ABC(int i = -1): abc(i) {}
-   virtual ~ABC() {}
+   BaseABC(int i = -1): abc(i) {}
+   virtual ~BaseABC() {}
    virtual int pv() = 0;
    int abc;
 };
 
-class Derived: public ABC {
+class Derived: public BaseABC {
 public:
    ~Derived() override {}
-   Derived(int i = -2): ABC(i+1), derived(i) {}
+   Derived(int i = -2): BaseABC(i+1), derived(i) {}
 
    int pv() override { return abc + derived; }
    int derived;
 };
 
 class Holder {
 public:
-   Holder(): fABC(0) {}
+   Holder(): fABC(nullptr) {}
    ~Holder() { delete fABC; }
 
    void Set(int i) { delete fABC; fABC = new Derived(i); }
 
-   ABC* fABC;
+   BaseABC* fABC;
 };
 

roottest/root/tree/branches/selection.xml

@@ -1,5 +1,5 @@
 <rootdict>
-   <class name="ABC"/>
+   <class name="BaseABC"/>
    <class name="Derived"/>
    <class name="Holder"/>
 </rootdict>