Fixed compiler warning C4267 'conversion from 'size_t' to 'type', possible loss of data'

BUG=angleproject:1120

Change-Id: I01ef10bea7f487c2b394d030c76628f38d2ea645
Reviewed-on: https://chromium-review.googlesource.com/292780
Tested-by: Cooper Partin <coopp@microsoft.com>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/compiler/translator/ParseContext.cpp b/src/compiler/translator/ParseContext.cpp
index 3700a9c..dd77b63 100644
--- a/src/compiler/translator/ParseContext.cpp
+++ b/src/compiler/translator/ParseContext.cpp
@@ -599,7 +599,7 @@
     {
         if (type->isUnsizedArray())
         {
-            type->setArraySize(function.getParamCount());
+            type->setArraySize(static_cast<int>(function.getParamCount()));
         }
         else if (static_cast<size_t>(type->getArraySize()) != function.getParamCount())
         {