[Sema] NFC: Move ContextualTypePurpose to constraint system header

Author: xedin

lib/Sema/ConstraintSystem.h

@@ -66,6 +66,46 @@ void *operator new(size_t bytes, swift::constraints::ConstraintSystem& cs,
 
 namespace swift {
 
+/// This specifies the purpose of the contextual type, when specified to
+/// typeCheckExpression.  This is used for diagnostic generation to produce more
+/// specified error messages when the conversion fails.
+///
+enum ContextualTypePurpose {
+  CTP_Unused,           ///< No contextual type is specified.
+  CTP_Initialization,   ///< Pattern binding initialization.
+  CTP_ReturnStmt,       ///< Value specified to a 'return' statement.
+  CTP_ReturnSingleExpr, ///< Value implicitly returned from a function.
+  CTP_YieldByValue,     ///< By-value yield operand.
+  CTP_YieldByReference, ///< By-reference yield operand.
+  CTP_ThrowStmt,        ///< Value specified to a 'throw' statement.
+  CTP_EnumCaseRawValue, ///< Raw value specified for "case X = 42" in enum.
+  CTP_DefaultParameter, ///< Default value in parameter 'foo(a : Int = 42)'.
+
+  /// Default value in @autoclosure parameter
+  /// 'foo(a : @autoclosure () -> Int = 42)'.
+  CTP_AutoclosureDefaultParameter,
+
+  CTP_CalleeResult,     ///< Constraint is placed on the result of a callee.
+  CTP_CallArgument,     ///< Call to function or operator requires type.
+  CTP_ClosureResult,    ///< Closure result expects a specific type.
+  CTP_ArrayElement,     ///< ArrayExpr wants elements to have a specific type.
+  CTP_DictionaryKey,    ///< DictionaryExpr keys should have a specific type.
+  CTP_DictionaryValue,  ///< DictionaryExpr values should have a specific type.
+  CTP_CoerceOperand,    ///< CoerceExpr operand coerced to specific type.
+  CTP_AssignSource,     ///< AssignExpr source operand coerced to result type.
+  CTP_SubscriptAssignSource, ///< AssignExpr source operand coerced to subscript
+                             ///< result type.
+  CTP_Condition,        ///< Condition expression of various statements e.g.
+                        ///< `if`, `for`, `while` etc.
+  CTP_ForEachStmt,      ///< "expression/sequence" associated with 'for-in' loop
+                        ///< is expected to conform to 'Sequence' protocol.
+  CTP_WrappedProperty,  ///< Property type expected to match 'wrappedValue' type
+  CTP_ComposedPropertyWrapper, ///< Composed wrapper type expected to match
+                               ///< former 'wrappedValue' type
+
+  CTP_CannotFail,       ///< Conversion can never fail. abort() if it does.
+};
+
 namespace constraints {
 
 /// Describes the algorithm to use for trailing closure matching.

lib/Sema/TypeChecker.h

@@ -112,48 +112,6 @@ class LookupTypeResult {
   }
 };
 
-/// This specifies the purpose of the contextual type, when specified to
-/// typeCheckExpression.  This is used for diagnostic generation to produce more
-/// specified error messages when the conversion fails.
-///
-enum ContextualTypePurpose {
-  CTP_Unused,           ///< No contextual type is specified.
-  CTP_Initialization,   ///< Pattern binding initialization.
-  CTP_ReturnStmt,       ///< Value specified to a 'return' statement.
-  CTP_ReturnSingleExpr, ///< Value implicitly returned from a function.
-  CTP_YieldByValue,     ///< By-value yield operand.
-  CTP_YieldByReference, ///< By-reference yield operand.
-  CTP_ThrowStmt,        ///< Value specified to a 'throw' statement.
-  CTP_EnumCaseRawValue, ///< Raw value specified for "case X = 42" in enum.
-  CTP_DefaultParameter, ///< Default value in parameter 'foo(a : Int = 42)'.
-
-  /// Default value in @autoclosure parameter
-  /// 'foo(a : @autoclosure () -> Int = 42)'.
-  CTP_AutoclosureDefaultParameter,
-
-  CTP_CalleeResult,     ///< Constraint is placed on the result of a callee.
-  CTP_CallArgument,     ///< Call to function or operator requires type.
-  CTP_ClosureResult,    ///< Closure result expects a specific type.
-  CTP_ArrayElement,     ///< ArrayExpr wants elements to have a specific type.
-  CTP_DictionaryKey,    ///< DictionaryExpr keys should have a specific type.
-  CTP_DictionaryValue,  ///< DictionaryExpr values should have a specific type.
-  CTP_CoerceOperand,    ///< CoerceExpr operand coerced to specific type.
-  CTP_AssignSource,     ///< AssignExpr source operand coerced to result type.
-  CTP_SubscriptAssignSource, ///< AssignExpr source operand coerced to subscript
-                             ///< result type.
-  CTP_Condition,        ///< Condition expression of various statements e.g.
-                        ///< `if`, `for`, `while` etc.
-  CTP_ForEachStmt,      ///< "expression/sequence" associated with 'for-in' loop
-                        ///< is expected to conform to 'Sequence' protocol.
-  CTP_WrappedProperty,  ///< Property type expected to match 'wrappedValue' type
-  CTP_ComposedPropertyWrapper, ///< Composed wrapper type expected to match
-                               ///< former 'wrappedValue' type
-
-  CTP_CannotFail,       ///< Conversion can never fail. abort() if it does.
-};
-
-
-
 /// Flags that can be used to control type checking.
 enum class TypeCheckExprFlags {
   /// Whether we know that the result of the expression is discarded.  This