Add tests

Author: matheusaaguiar

test/libsolidity/syntaxTests/storageLayoutSpecifier/layout_already_specified_in_ancestor_contract.sol

@@ -4,5 +4,4 @@ contract B is A {}
 
 contract C is B layout at 0xABCD {}
 // ----
-// TypeError 8894: (32-50): Storage layout can only be specified in the most derived contract.
-// TypeError 8894: (52-87): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (46-47): Storage layout can only be specified in the most derived contract.

test/libsolidity/syntaxTests/storageLayoutSpecifier/layout_specified_by_ancestor_contract_module.sol

@@ -0,0 +1,13 @@
+==== Source: M ====
+contract A layout at 0x1234 {}
+
+==== Source: N ====
+contract A {}
+
+==== Source: C ====
+import "M" as M;
+import "N" as N;
+
+contract C is M.A, N.A layout at 0xABCD {}
+// ----
+// TypeError 8894: (C:49-52): Storage layout can only be specified in the most derived contract.

test/libsolidity/syntaxTests/storageLayoutSpecifier/layout_specified_by_ancestor_contract_multiple_inheritance.sol

@@ -0,0 +1,16 @@
+contract A layout at 1 {}
+contract B is A layout at 2 {}
+
+contract C1 is B {}
+contract C2 is A, B {}
+contract C3 is B {}
+
+contract D1 is C1 {}
+contract D2 is C2 {}
+contract D3 is C3 {}
+// ----
+// TypeError 8894: (40-41): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (73-74): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (93-94): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (96-97): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (116-117): Storage layout can only be specified in the most derived contract.

test/libsolidity/syntaxTests/storageLayoutSpecifier/layout_specified_by_first_ancestor_contract.sol

@@ -3,6 +3,4 @@ contract B is A {}
 contract C is B {}
 contract D is C {}
 // ----
-// TypeError 8894: (27-45): Storage layout can only be specified in the most derived contract.
-// TypeError 8894: (46-64): Storage layout can only be specified in the most derived contract.
-// TypeError 8894: (65-83): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (41-42): Storage layout can only be specified in the most derived contract.

test/libsolidity/syntaxTests/storageLayoutSpecifier/layout_specified_by_last_ancestor_contract.sol

@@ -3,4 +3,4 @@ contract B is A {}
 contract C is B layout at 42 {}
 contract D is C {}
 // ----
-// TypeError 8894: (65-83): Storage layout can only be specified in the most derived contract.
+// TypeError 8894: (79-80): Storage layout can only be specified in the most derived contract.