Remove grab-bag includes of v8.h from everywhere.

test/cctest/gay-precision.h

 // Copyright 2006-2008 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 10 matching lines @@
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef GAY_PRECISION_H_
 #define GAY_PRECISION_H_
 
+#include "src/vector.h"
+
 namespace v8 {
 namespace internal {
 
 struct PrecomputedPrecision {
   double v;
   int number_digits;
   const char* representation;
   int decimal_point;
 };
 
 // Returns precomputed values of dtoa. The strings have been generated using
 // Gay's dtoa in mode "precision".
 Vector<const PrecomputedPrecision> PrecomputedPrecisionRepresentations();
 
 } }  // namespace v8::internal
 
 #endif  // GAY_PRECISION_H_