Add source locations to syntax test expectations.

test/libsolidity/syntaxTests/scoping/double_function_declaration.sol

@@ -3,4 +3,4 @@ contract test {
     function fun() public { }
 }
 // ----
-// DeclarationError: Function with same name and arguments defined twice.
+// DeclarationError: (20-45): Function with same name and arguments defined twice.

test/libsolidity/syntaxTests/scoping/double_variable_declaration_disjoint_scope.sol

@@ -5,4 +5,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Identifier already declared.
+// DeclarationError: (77-83): Identifier already declared.

test/libsolidity/syntaxTests/scoping/double_variable_declaration_disjoint_scope_050.sol

@@ -6,5 +6,5 @@ contract test {
     }
 }
 // ----
-// Warning: Unused local variable.
-// Warning: Unused local variable.
+// Warning: (87-93): Unused local variable.
+// Warning: (107-113): Unused local variable.

test/libsolidity/syntaxTests/scoping/double_variable_declaration_disjoint_scope_activation.sol

@@ -5,4 +5,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Identifier already declared.
+// DeclarationError: (75-81): Identifier already declared.

test/libsolidity/syntaxTests/scoping/double_variable_declaration_disjoint_scope_activation_050.sol

@@ -6,5 +6,5 @@ contract test {
     }
 }
 // ----
-// Warning: Unused local variable.
-// Warning: Unused local variable.
+// Warning: (87-93): Unused local variable.
+// Warning: (105-111): Unused local variable.

test/libsolidity/syntaxTests/scoping/name_shadowing.sol

@@ -3,5 +3,4 @@ contract test {
     function f() pure public { uint32 variable; variable = 2; }
 }
 // ----
-// Warning: This declaration shadows an existing declaration.
-
+// Warning: (69-84): This declaration shadows an existing declaration.

test/libsolidity/syntaxTests/scoping/scoping.sol

@@ -8,4 +8,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Undeclared identifier.
+// DeclarationError: (123-124): Undeclared identifier.

test/libsolidity/syntaxTests/scoping/scoping_activation.sol

@@ -6,4 +6,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Undeclared identifier. Did you mean "x"?
+// DeclarationError: (85-86): Undeclared identifier. Did you mean "x"?

test/libsolidity/syntaxTests/scoping/scoping_for3.sol

@@ -8,4 +8,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Undeclared identifier.
+// DeclarationError: (154-155): Undeclared identifier.

test/libsolidity/syntaxTests/scoping/scoping_for_decl_in_body.sol

@@ -7,4 +7,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Undeclared identifier.
+// DeclarationError: (93-94): Undeclared identifier.

test/libsolidity/syntaxTests/scoping/scoping_self_use_050.sol

@@ -5,4 +5,4 @@ contract test {
     }
 }
 // ----
-// DeclarationError: Undeclared identifier. Did you mean "a"?
+// DeclarationError: (94-95): Undeclared identifier. Did you mean "a"?