Set state mutability of function type members `gas and value` to pure.

test/libsolidity/syntaxTests/viewPureChecker/gas_value_without_call.sol

@@ -0,0 +1,13 @@
+contract C {
+    function f() external payable {}
+	function g(address a) external pure {
+		a.call.value(42);
+		a.call.gas(42);
+		a.staticcall.gas(42);
+		a.delegatecall.gas(42);
+	}
+	function h() external view {
+		this.f.value(42);
+		this.f.gas(42);
+	}
+}

test/libsolidity/syntaxTests/viewPureChecker/gas_with_call_nonpayable.sol

@@ -0,0 +1,16 @@
+contract C {
+	function f(address a) external view returns (bool success) {
+		(success,) = a.call.gas(42)("");
+	}
+	function g(address a) external view returns (bool success) {
+		(success,) = a.call.gas(42)("");
+	}
+	function h() external payable {}
+	function i() external view {
+		this.h.gas(42)();
+	}
+}
+// ----
+// TypeError: (90-108): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.
+// TypeError: (190-208): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.
+// TypeError: (279-295): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.

test/libsolidity/syntaxTests/viewPureChecker/staticcall_gas_view.sol

@@ -0,0 +1,11 @@
+contract C {
+    function f() external view {}
+	function test(address a) external view returns (bool status) {
+		// This used to incorrectly raise an error about violating the view mutability.
+		(status,) = a.staticcall.gas(42)("");
+		this.f.gas(42)();
+	}
+}
+// ====
+// EVMVersion: >=byzantium
+// ----

test/libsolidity/syntaxTests/viewPureChecker/value_with_call_nonpayable.sol

@@ -0,0 +1,16 @@
+contract C {
+	function f(address a) external view returns (bool success) {
+		(success,) = a.call.value(42)("");
+	}
+	function g(address a) external view returns (bool success) {
+		(success,) = a.call.value(42)("");
+	}
+	function h() external payable {}
+	function i() external view {
+		this.h.value(42)();
+	}
+}
+// ----
+// TypeError: (90-110): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.
+// TypeError: (192-212): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.
+// TypeError: (283-301): Function declared as view, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.