Related: fdo#49208 implement operator== with faster equals

we have an optimized equals which checks that the strings being
compared for equality share the same underlying pImpl, but out
operator== implementations don't use it!

Change-Id: Ie5c464494ff875315a5ca369a2da80c22c29f431

sal/inc/rtl/string.hxx

@@ -712,7 +712,7 @@ public:
     }
 
     friend sal_Bool     operator == ( const OString& rStr1, const OString& rStr2 ) SAL_THROW(())
-                        { return rStr1.getLength() == rStr2.getLength() && rStr1.compareTo( rStr2 ) == 0; }
+                        { return rStr1.equals(rStr2); }
     friend sal_Bool     operator != ( const OString& rStr1,     const OString& rStr2 ) SAL_THROW(())
                         { return !(operator == ( rStr1, rStr2 )); }
     friend sal_Bool     operator <  ( const OString& rStr1,    const OString& rStr2 ) SAL_THROW(())

sal/inc/rtl/ustring.hxx

@@ -988,7 +988,7 @@ public:
     }
 
     friend sal_Bool     operator == ( const OUString& rStr1,    const OUString& rStr2 ) SAL_THROW(())
-                        { return rStr1.getLength() == rStr2.getLength() && rStr1.compareTo( rStr2 ) == 0; }
+                        { return rStr1.equals(rStr2); }
     friend sal_Bool     operator == ( const OUString& rStr1,    const sal_Unicode * pStr2 ) SAL_THROW(())
                         { return rStr1.compareTo( pStr2 ) == 0; }
     friend sal_Bool     operator == ( const sal_Unicode * pStr1,    const OUString& rStr2 ) SAL_THROW(())