C++: Move the rest of of StdSequenceContainerBeginEnd into BeginOrEndFunction.

cpp/ql/src/semmle/code/cpp/models/implementations/Iterator.qll

@@ -280,7 +280,9 @@ class IteratorArrayMemberOperator extends MemberFunction, TaintFunction, Iterato
  */
 class BeginOrEndFunction extends MemberFunction, TaintFunction {
   BeginOrEndFunction() {
-    this.hasName(["begin", "cbegin", "rbegin", "crbegin", "end", "cend", "rend", "crend"]) and
+    this
+        .hasName(["begin", "cbegin", "rbegin", "crbegin", "end", "cend", "rend", "crend",
+              "before_begin", "cbefore_begin"]) and
     this.getType().getUnspecifiedType() instanceof Iterator
   }
 

cpp/ql/src/semmle/code/cpp/models/implementations/StdContainer.qll

@@ -170,22 +170,6 @@ class StdSequenceContainerAssign extends TaintFunction {
   }
 }
 
-/**
- * The standard container `before_begin` and `cbefore_begin` functions.
- */
-class StdSequenceContainerBeginEnd extends TaintFunction {
-  StdSequenceContainerBeginEnd() {
-    this
-        .hasQualifiedName("std", "forward_list",
-          ["before_begin", "cbefore_begin"])
-  }
-
-  override predicate hasTaintFlow(FunctionInput input, FunctionOutput output) {
-    input.isQualifierObject() and
-    output.isReturnValue()
-  }
-}
-
 /**
  * The standard container `swap` functions.
  */