Refactor BasicBlock, no inheritance from GenericNode

src/compiler/code-generator.h

Index: src/compiler/code-generator.h
diff --git a/src/compiler/code-generator.h b/src/compiler/code-generator.h
index ddc2f9adb6fd55abd8ae91612cdc069bf4a42454..ae9355137f376f28b0e7ca0bf8c1055a408917a9 100644
--- a/src/compiler/code-generator.h
+++ b/src/compiler/code-generator.h
@@ -41,8 +41,8 @@ class CodeGenerator FINAL : public GapResolver::Assembler {
   // Checks if {block} will appear directly after {current_block_} when
   // assembling code, in which case, a fall-through can be used.
   bool IsNextInAssemblyOrder(const BasicBlock* block) const {
-    return block->rpo_number_ == (current_block_->rpo_number_ + 1) &&
-           block->deferred_ == current_block_->deferred_;
+    return block->rpo_number() == (current_block_->rpo_number() + 1) &&
+           block->deferred() == current_block_->deferred();
   }
 
   // Record a safepoint with the given pointer map.