Fix lint errors - spacing and formatting.

src/register-allocator-ia32.h

 // Copyright 2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 63 matching lines @@
   int ref_counts_[kNumRegisters];
 };
 
 
 // -------------------------------------------------------------------------
 // Register allocator
 //
 
 class RegisterAllocator BASE_EMBEDDED {
  public:
-  RegisterAllocator(CodeGenerator* cgen) : code_generator_(cgen) {}
+  explicit RegisterAllocator(CodeGenerator* cgen) : code_generator_(cgen) {}
 
   int num_registers() const { return RegisterFile::kNumRegisters; }
 
   int count(int reg_code) { return registers_.count(reg_code); }
 
   // Explicitly record a reference to a register.
   void Use(Register reg) { registers_.Use(reg); }
 
   // Explicitly record that a register will no longer be used.
   void Unuse(Register reg) { registers_.Unuse(reg); }
@@ skipping 11 matching lines @@
   Register AllocateWithoutSpilling();
 
  private:
   CodeGenerator* code_generator_;
   RegisterFile registers_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_REGISTER_ALLOCATOR_IA32_H_