Update clippy settings and fix a few clippy warnings.

lib/wasm/src/code_translator.rs

@@ -37,7 +37,7 @@ use std::{i32, u32};
 use wasmparser::{MemoryImmediate, Operator};
 
 // Clippy warns about "flags: _" but its important to document that the flags field is ignored
-#[cfg_attr(feature = "cargo-clippy", allow(unneeded_field_pattern))]
+#[cfg_attr(feature = "cargo-clippy", allow(clippy::unneeded_field_pattern))]
 /// Translates wasm operators into Cranelift IR instructions. Returns `true` if it inserted
 /// a return.
 pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
@@ -894,7 +894,7 @@ pub fn translate_operator<FE: FuncEnvironment + ?Sized>(
 }
 
 // Clippy warns us of some fields we are deliberately ignoring
-#[cfg_attr(feature = "cargo-clippy", allow(unneeded_field_pattern))]
+#[cfg_attr(feature = "cargo-clippy", allow(clippy::unneeded_field_pattern))]
 /// Deals with a Wasm instruction located in an unreachable portion of the code. Most of them
 /// are dropped but special ones like `End` or `Else` signal the potential end of the unreachable
 /// portion so the translation state must be updated accordingly.

lib/wasm/src/environ/dummy.rs

@@ -187,7 +187,7 @@ impl<'dummy_environment> FuncEnvironment for DummyFuncEnvironment<'dummy_environ
         let vmctx = func.create_global_value(ir::GlobalValueData::VMContext {});
         GlobalVariable::Memory {
             gv: vmctx,
-            offset: offset,
+            offset,
             ty: self.mod_info.globals[index].entity.ty,
         }
     }

lib/wasm/src/environ/spec.rs

@@ -164,7 +164,7 @@ pub trait FuncEnvironment {
     /// The signature `sig_ref` was previously created by `make_indirect_sig()`.
     ///
     /// Return the call instruction whose results are the WebAssembly return values.
-    #[cfg_attr(feature = "cargo-clippy", allow(too_many_arguments))]
+    #[cfg_attr(feature = "cargo-clippy", allow(clippy::too_many_arguments))]
     fn translate_call_indirect(
         &mut self,
         pos: FuncCursor,

lib/wasm/src/lib.rs

@@ -13,10 +13,7 @@
 #![warn(unused_import_braces)]
 #![cfg_attr(feature = "std", deny(unstable_features))]
 #![cfg_attr(feature = "clippy", plugin(clippy(conf_file = "../../clippy.toml")))]
-#![cfg_attr(
-    feature = "cargo-clippy",
-    allow(new_without_default, new_without_default_derive)
-)]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::new_without_default))]
 #![cfg_attr(
     feature = "cargo-clippy",
     warn(