[interpreter] Move temporary register allocator into own file.

test/cctest/interpreter/test-bytecode-generator.cc

Index: test/cctest/interpreter/test-bytecode-generator.cc
diff --git a/test/cctest/interpreter/test-bytecode-generator.cc b/test/cctest/interpreter/test-bytecode-generator.cc
index b730fa63ebe15a0ff2f637a3da14b19dda0cc968..af83799c50f02914d8d533e04411ca8858e3485c 100644
--- a/test/cctest/interpreter/test-bytecode-generator.cc
+++ b/test/cctest/interpreter/test-bytecode-generator.cc
@@ -7276,9 +7276,6 @@ TEST(DeleteLookupSlotInEval) {
 }
 
 TEST(WideRegisters) {
-  InitializedHandleScope handle_scope;
-  BytecodeGeneratorHelper helper;
-
   // Prepare prologue that creates frame for lots of registers.
   std::ostringstream os;
   for (size_t i = 0; i < 157; ++i) {
@@ -7493,6 +7490,9 @@ TEST(WideRegisters) {
            B(Return),                                                //
        }}};
 
+  InitializedHandleScope handle_scope;
+  BytecodeGeneratorHelper helper;
+
   for (size_t i = 0; i < arraysize(snippets); ++i) {
     std::string body = prologue + snippets[i].code_snippet;
     Handle<BytecodeArray> bytecode_array =