Linux: fix compilation error with gcc 4.5.

Avoid a gcc 4.5 warning/error for values that aren't part
of NPNVariable. Also drop some unnecessary static_casts by
swapping from an int to a size_t in TemplateURLRef's
Replacement struct and use platform specific NULL or 0
constants in a couple of places.

BUG=43341
TEST=chrome target compiles with gcc 4.5.

Review URL: http://codereview.chromium.org/2019002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@46889 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/search_engines/template_url_unittest.cc b/chrome/browser/search_engines/template_url_unittest.cc
index b2ef832b..5f9bfff 100644
--- a/chrome/browser/search_engines/template_url_unittest.cc
+++ b/chrome/browser/search_engines/template_url_unittest.cc
@@ -421,7 +421,7 @@
   EXPECT_TRUE(url_ref.ParseParameter(0, 12, &parsed_url, &replacements));
   EXPECT_EQ(std::wstring(), parsed_url);
   ASSERT_EQ(1U, replacements.size());
-  EXPECT_EQ(0, replacements[0].index);
+  EXPECT_EQ(static_cast<size_t>(0), replacements[0].index);
   EXPECT_EQ(TemplateURLRef::SEARCH_TERMS, replacements[0].type);
 }
 
@@ -468,7 +468,7 @@
   EXPECT_EQ(L"{}{}",
             url_ref.ParseURL(L"{}{{searchTerms}}", &replacements, &valid));
   ASSERT_EQ(1U, replacements.size());
-  EXPECT_EQ(3, replacements[0].index);
+  EXPECT_EQ(static_cast<size_t>(3), replacements[0].index);
   EXPECT_EQ(TemplateURLRef::SEARCH_TERMS, replacements[0].type);
   EXPECT_TRUE(valid);
 }
@@ -479,7 +479,7 @@
   bool valid = false;
   EXPECT_EQ(L"{", url_ref.ParseURL(L"{{searchTerms}", &replacements, &valid));
   ASSERT_EQ(1U, replacements.size());
-  EXPECT_EQ(1, replacements[0].index);
+  EXPECT_EQ(static_cast<size_t>(1), replacements[0].index);
   EXPECT_EQ(TemplateURLRef::SEARCH_TERMS, replacements[0].type);
   EXPECT_TRUE(valid);
 }