trans: Move TransItem to its own module.

Author: michaelwoerister

src/librustc_trans/base.rs

@@ -59,7 +59,7 @@ use callee::{Callee, CallArgs, ArgExprs, ArgVals};
 use cleanup::{self, CleanupMethods, DropHint};
 use closure;
 use common::{Block, C_bool, C_bytes_in_context, C_i32, C_int, C_uint, C_integral};
-use collector::{self, TransItem, TransItemState, TransItemCollectionMode};
+use collector::{self, TransItemState, TransItemCollectionMode};
 use common::{C_null, C_struct_in_context, C_u64, C_u8, C_undef};
 use common::{CrateContext, DropFlagHintsMap, Field, FunctionContext};
 use common::{Result, NodeIdAndSpan, VariantInfo};
@@ -82,6 +82,7 @@ use mir;
 use monomorphize::{self, Instance};
 use partitioning::{self, PartitioningStrategy, InstantiationMode, CodegenUnit};
 use symbol_names_test;
+use trans_item::TransItem;
 use tvec;
 use type_::Type;
 use type_of;