CompleteParserRecorder: Don't do zero-sized allocations.

Instead, we should use Collector::kMinCapacity.

R=jochen@chromium.org
BUG=v8:3727
LOG=N

Review URL: https://codereview.chromium.org/847823002

Cr-Commit-Position: refs/heads/master@{#26030}

src/preparse-data.cc

@@ -13,8 +13,7 @@ namespace v8 {
 namespace internal {
 
 
-CompleteParserRecorder::CompleteParserRecorder()
-    : function_store_(0) {
+CompleteParserRecorder::CompleteParserRecorder() {
   preamble_[PreparseDataConstants::kMagicOffset] =
       PreparseDataConstants::kMagicNumber;
   preamble_[PreparseDataConstants::kVersionOffset] =