C#: Remove hasNotNullFlowState and hasMaybeNullFlowState

Author: hvitved

csharp/ql/lib/semmle/code/csharp/controlflow/Guards.qll

@@ -1186,8 +1186,6 @@ module Internal {
     or
     e instanceof ArrayCreation
     or
-    e.hasNotNullFlowState()
-    or
     e.hasValue() and
     exists(Expr stripped | stripped = e.stripCasts() |
       not stripped instanceof NullLiteral and

csharp/ql/lib/semmle/code/csharp/exprs/Expr.qll

@@ -108,12 +108,6 @@ class Expr extends ControlFlowElement, @expr {
    * that uses the result of this expression.
    */
   override Element getParent() { result = ControlFlowElement.super.getParent() }
-
-  /** Holds if the nullable flow state of this expression is not null. */
-  predicate hasNotNullFlowState() { expr_flowstate(this, 1) }
-
-  /** Holds if the nullable flow state of this expression may be null. */
-  predicate hasMaybeNullFlowState() { expr_flowstate(this, 2) }
 }
 
 /**