[analyzer] SATestBuild: Don't require reference results to have logs.

The Logs directory isn't used for testing, so it's filtered out ahead of
time. However, there's then no reason to include it in version control at
all. Don't error if it's not present.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183689 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/analyzer/SATestBuild.py b/utils/analyzer/SATestBuild.py
index 8e09a7a..eb77964 100755
--- a/utils/analyzer/SATestBuild.py
+++ b/utils/analyzer/SATestBuild.py
@@ -413,8 +413,10 @@
     RefList = glob.glob(RefDir + "/*") 
     NewList = glob.glob(NewDir + "/*")
     
-    # Log folders are also located in the results dir, so ignore them. 
-    RefList.remove(os.path.join(RefDir, LogFolderName))
+    # Log folders are also located in the results dir, so ignore them.
+    RefLogDir = os.path.join(RefDir, LogFolderName)
+    if RefLogDir in RefList:
+        RefList.remove(RefLogDir)
     NewList.remove(os.path.join(NewDir, LogFolderName))
     
     if len(RefList) == 0 or len(NewList) == 0: