Modify big integer library

pdfium.gyp

Index: pdfium.gyp
diff --git a/pdfium.gyp b/pdfium.gyp
index 606925c5e234419f220ad10e76a6dda124a6799b..7e7dba9dfc56c58b82ccf796529446de5be82cdd 100644
--- a/pdfium.gyp
+++ b/pdfium.gyp
@@ -36,6 +36,7 @@
       'type': 'static_library',
       'dependencies': [
         'safemath',
+        'bigint',
         'fdrm',
         'fpdfdoc',
         'fpdfapi',
@@ -137,6 +138,22 @@
       ],
     },
     {
+      'target_name': 'bigint',
+      'type': 'static_library',
+      'sources': [
+        'third_party/bigint/BigInteger.hh',
+        'third_party/bigint/BigIntegerLibrary.hh',
+        'third_party/bigint/BigIntegerUtils.hh',
+        'third_party/bigint/BigUnsigned.hh',
+        'third_party/bigint/NumberlikeArray.hh',
+        'third_party/bigint/BigUnsignedInABase.hh',
+        'third_party/bigint/BigInteger.cc',
+        'third_party/bigint/BigIntegerUtils.cc',
+        'third_party/bigint/BigUnsigned.cc',
+        'third_party/bigint/BigUnsignedInABase.cc',
+      ],
+    },
+    {
       'target_name': 'fdrm',
       'type': 'static_library',
       'ldflags': [ '-L<(PRODUCT_DIR)',],