Merge pull request #6812 from ethereum/asmCallvalue

Do not require payable for callvalue instruction.

test/libsolidity/syntaxTests/viewPureChecker/callvalue_nonpayable_assembly_fallback.sol

@@ -8,4 +8,3 @@ contract C
     }
 }
 // ----
-// TypeError: (92-103): "msg.value" and "callvalue()" can only be used in payable public functions. Make the function "payable" or use an internal function to avoid this error.

test/libsolidity/syntaxTests/viewPureChecker/callvalue_nonpayable_assembly_function.sol

@@ -7,4 +7,4 @@ contract C
     }
 }
 // ----
-// TypeError: (81-92): "msg.value" and "callvalue()" can only be used in payable public functions. Make the function "payable" or use an internal function to avoid this error.
+// Warning: (17-108): Function state mutability can be restricted to view

test/libsolidity/syntaxTests/viewPureChecker/callvalue_nonpayable_assembly_function_internal.sol

@@ -9,3 +9,5 @@ contract C
 		return f();
 	}
 }
+// ----
+// Warning: (17-121): Function state mutability can be restricted to view

test/libsolidity/syntaxTests/viewPureChecker/callvalue_nonpayable_assembly_function_modifier.sol

@@ -11,4 +11,3 @@ contract C
     }
 }
 // ----
-// TypeError: (99-100): This modifier uses "msg.value" or "callvalue()" and thus the function has to be payable or internal.