Fix newly discovered presubmit errors.

src/interpreter-irregexp.cc

Index: src/interpreter-irregexp.cc
diff --git a/src/interpreter-irregexp.cc b/src/interpreter-irregexp.cc
index 626090e455785affb7db5ba4b02ffd6fe0b401b6..7f51d5e410a7822563aaa4c1e449183b6fb6b181 100644
--- a/src/interpreter-irregexp.cc
+++ b/src/interpreter-irregexp.cc
@@ -136,9 +136,7 @@ static int32_t Load16Aligned(const byte* pc) {
 // matching terminates.
 class BacktrackStack {
  public:
-  explicit BacktrackStack() {
-    data_ = NewArray<int>(kBacktrackStackSize);
-  }
+  BacktrackStack() { data_ = NewArray<int>(kBacktrackStackSize); }
 
   ~BacktrackStack() {
     DeleteArray(data_);