Remove CFX_SegmentedArray use from master

third_party/base/stl_util.h

Index: third_party/base/stl_util.h
diff --git a/third_party/base/stl_util.h b/third_party/base/stl_util.h
index 32656038c145c2ba33a2c91edbd27afac4d8df09..7f1d38bf4026dff786efc7c04644d120e8df4307 100644
--- a/third_party/base/stl_util.h
+++ b/third_party/base/stl_util.h
@@ -5,6 +5,8 @@
 #ifndef PDFIUM_THIRD_PARTY_BASE_STL_UTIL_H_
 #define PDFIUM_THIRD_PARTY_BASE_STL_UTIL_H_
 
+#include "third_party/base/numerics/safe_conversions.h"
+
 namespace pdfium {
 
 // Test to see if a set, map, hash_set or hash_map contains a particular key.
@@ -22,6 +24,13 @@ bool ContainsValue(const Collection& collection, const Value& value) {
          collection.end();
 }
 
+// Convenience routine for "int-fected" code, so that the stl collection
+// size_t size() method return values will be checked.
+template <typename ResultType, typename Collection>
+ResultType CollectionSize(const Collection& collection) {
+  return pdfium::base::checked_cast<ResultType, size_t>(collection.size());
+}
+
 }  // namespace pdfium
 
 #endif  // PDFIUM_THIRD_PARTY_BASE_STL_UTIL_H_