win: fixes for Windows x64

minidump/minidump_simple_string_dictionary_writer_test.cc

Index: minidump/minidump_simple_string_dictionary_writer_test.cc
diff --git a/minidump/minidump_simple_string_dictionary_writer_test.cc b/minidump/minidump_simple_string_dictionary_writer_test.cc
index f1f6814f9fe390e2598e0bf97f1e61d54778a1db..0f9a71bd288c68302916628bc116185189223350 100644
--- a/minidump/minidump_simple_string_dictionary_writer_test.cc
+++ b/minidump/minidump_simple_string_dictionary_writer_test.cc
@@ -31,9 +31,9 @@ const MinidumpSimpleStringDictionary* MinidumpSimpleStringDictionaryAtStart(
     const std::string& file_contents,
     size_t count) {
   MINIDUMP_LOCATION_DESCRIPTOR location_descriptor;
-  location_descriptor.DataSize =
+  location_descriptor.DataSize = static_cast<uint32_t>(
       sizeof(MinidumpSimpleStringDictionary) +
-      count * sizeof(MinidumpSimpleStringDictionaryEntry);
+      count * sizeof(MinidumpSimpleStringDictionaryEntry));
   location_descriptor.Rva = 0;
   return MinidumpWritableAtLocationDescriptor<MinidumpSimpleStringDictionary>(
       file_contents, location_descriptor);