Mark single-argument inline constructors as 'explicit'.

src/mips/virtual-frame-mips.h

 // Copyright 2010 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 88 matching lines @@
     RegisterAllocationScope() {}
   };
 
   // An illegal index into the virtual frame.
   static const int kIllegalIndex = -1;
 
   // Construct an initial virtual frame on entry to a JS function.
   inline VirtualFrame();
 
   // Construct an invalid virtual frame, used by JumpTargets.
-  inline VirtualFrame(InvalidVirtualFrameInitializer* dummy);
+  explicit inline VirtualFrame(InvalidVirtualFrameInitializer* dummy);
 
   // Construct a virtual frame as a clone of an existing one.
   explicit inline VirtualFrame(VirtualFrame* original);
 
   inline CodeGenerator* cgen() const;
   inline MacroAssembler* masm();
 
   // The number of elements on the virtual frame.
   int element_count() const { return element_count_; }
 
@@ skipping 401 matching lines @@
     }
   }
   friend class JumpTarget;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_MIPS_VIRTUAL_FRAME_MIPS_H_