Reduce signed/unsigned comparison warnings

core/fxcodec/jbig2/JBig2_Context.cpp

Index: core/fxcodec/jbig2/JBig2_Context.cpp
diff --git a/core/fxcodec/jbig2/JBig2_Context.cpp b/core/fxcodec/jbig2/JBig2_Context.cpp
index da020a6a75d8b12b0bcc19de4b8c583f3b152805..c3006c16391d7d2c5454b6e502a3ccf43922c1ab 100644
--- a/core/fxcodec/jbig2/JBig2_Context.cpp
+++ b/core/fxcodec/jbig2/JBig2_Context.cpp
@@ -1277,7 +1277,7 @@ JBig2HuffmanCode* CJBig2_Context::decodeSymbolIDHuffmanTable(
   const size_t kRunCodesSize = 35;
   int32_t runcodes[kRunCodesSize];
   int32_t runcodes_len[kRunCodesSize];
-  for (int32_t i = 0; i < kRunCodesSize; ++i) {
+  for (size_t i = 0; i < kRunCodesSize; ++i) {
     if (pStream->readNBits(4, &runcodes_len[i]) != 0)
       return nullptr;
   }
@@ -1288,7 +1288,7 @@ JBig2HuffmanCode* CJBig2_Context::decodeSymbolIDHuffmanTable(
   int32_t run;
   int32_t i = 0;
   while (i < (int)SBNUMSYMS) {
-    int32_t j;
+    size_t j;
     int32_t nVal = 0;
     int32_t nBits = 0;
     FX_DWORD nTemp;
@@ -1327,11 +1327,11 @@ JBig2HuffmanCode* CJBig2_Context::decodeSymbolIDHuffmanTable(
     if (run > 0) {
       if (i + run > (int)SBNUMSYMS)
         return nullptr;
-      for (j = 0; j < run; ++j) {
+      for (int32_t k = 0; k < run; ++k) {
         if (runcode == 32 && i > 0) {
-          SBSYMCODES.get()[i + j].codelen = SBSYMCODES.get()[i - 1].codelen;
+          SBSYMCODES.get()[i + k].codelen = SBSYMCODES.get()[i - 1].codelen;
         } else {
-          SBSYMCODES.get()[i + j].codelen = 0;
+          SBSYMCODES.get()[i + k].codelen = 0;
         }
       }
       i += run;