Bug 559113 - Fix dangling FILE pointer in GCMETER code. r=jorendorff.

js/src/jsgc.cpp

@@ -2843,11 +2843,11 @@ void dumpGCTimer(GCTimer *gcT, uint64 firstEnter, bool lastGC)
 
     if (!gcFile) {
         gcFile = fopen("gcTimer.dat", "w");
-        JS_ASSERT(gcFile);
         
         fprintf(gcFile, "     AppTime,  Total,   Mark,  Sweep, FinObj, ");
         fprintf(gcFile, "FinStr, FinDbl, Destroy,  newChunks, destoyChunks\n");
     }
+    JS_ASSERT(gcFile);
     fprintf(gcFile, "%12.1f, %6.1f, %6.1f, %6.1f, %6.1f, %6.1f, %6.1f, %7.1f, ",
             (double)(gcT->enter - firstEnter) / 1E6, 
             (double)(gcT->end-gcT->enter) / 1E6, 
@@ -2860,8 +2860,10 @@ void dumpGCTimer(GCTimer *gcT, uint64 firstEnter, bool lastGC)
     fprintf(gcFile, "%10d, %10d \n", newChunkCount, destroyChunkCount);
     fflush(gcFile);
 
-    if (lastGC)
+    if (lastGC) {
         fclose(gcFile);
+        gcFile = NULL;
+    }
 }
 
 # define GCTIMER_PARAM      , GCTimer &gcTimer