Code change to avoid signed/unsigned mismatch warnings

core/fpdftext/fpdf_text_int_unittest.cpp

 // Copyright 2015 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/fpdftext/fpdf_text_int.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 // Class to help test functions in CPDF_LinkExtract class.
 class CPDF_TestLinkExtract : public CPDF_LinkExtract {
  private:
   // Add test cases as friends to access protected member functions.
   // Access CheckMailLink.
   FRIEND_TEST(fpdf_text_int, CheckMailLink);
 };
 
 TEST(fpdf_text_int, CheckMailLink) {
   CPDF_TestLinkExtract extractor;
   // Check cases that fail to extract valid mail link.
   const wchar_t* invalid_strs[] = {
       L"",
       L"peter.pan",       // '@' is required.
       L"abc@server",      // Domain name needs at least one '.'.
       L"abc.@gmail.com",  // '.' can not immediately precede '@'.
       L"abc@xyz&q.org",   // Domain name should not contain '&'.
       L"abc@.xyz.org",    // Domain name should not start with '.'.
       L"fan@g..com"       // Domain name should not have consecutive '.'
   };
-  for (int i = 0; i < FX_ArraySize(invalid_strs); ++i) {
+  for (size_t i = 0; i < FX_ArraySize(invalid_strs); ++i) {
     CFX_WideString text_str(invalid_strs[i]);
     EXPECT_FALSE(extractor.CheckMailLink(text_str));
   }
 
   // Check cases that can extract valid mail link.
   // An array of {input_string, expected_extracted_email_address}.
   const wchar_t* valid_strs[][2] = {
       {L"peter@abc.d", L"peter@abc.d"},
       {L"red.teddy.b@abc.com", L"red.teddy.b@abc.com"},
       {L"abc_@gmail.com", L"abc_@gmail.com"},  // '_' is ok before '@'.
       {L"dummy-hi@gmail.com",
        L"dummy-hi@gmail.com"},                  // '-' is ok in user name.
       {L"a..df@gmail.com", L"df@gmail.com"},    // Stop at consecutive '.'.
       {L".john@yahoo.com", L"john@yahoo.com"},  // Remove heading '.'.
       {L"abc@xyz.org?/", L"abc@xyz.org"},       // Trim ending invalid chars.
       {L"fan{abc@xyz.org", L"abc@xyz.org"},     // Trim beginning invalid chars.
       {L"fan@g.com..", L"fan@g.com"},           // Trim the ending periods.
       {L"CAP.cap@Gmail.Com", L"CAP.cap@Gmail.Com"},  // Keep the original case.
   };
-  for (int i = 0; i < FX_ArraySize(valid_strs); ++i) {
+  for (size_t i = 0; i < FX_ArraySize(valid_strs); ++i) {
     CFX_WideString text_str(valid_strs[i][0]);
     CFX_WideString expected_str(L"mailto:");
     expected_str += valid_strs[i][1];
     EXPECT_TRUE(extractor.CheckMailLink(text_str));
     EXPECT_STREQ(text_str.c_str(), expected_str.c_str());
   }
 }