Don't set modification times in aapt zip entries

Use a modification timestamp of 0 for all files
inside the zip archive to make the build repeatable.

Change-Id: Ie6e57329469b99c6f93cb0a6083e0c402be99815
diff --git a/tools/aapt/ZipFile.cpp b/tools/aapt/ZipFile.cpp
index 36f4e73..2840826 100644
--- a/tools/aapt/ZipFile.cpp
+++ b/tools/aapt/ZipFile.cpp
@@ -364,7 +364,7 @@
     long lfhPosn, startPosn, endPosn, uncompressedLen;
     FILE* inputFp = NULL;
     unsigned long crc;
-    time_t modWhen;
+    time_t modWhen = 0;
 
     if (mReadOnly)
         return INVALID_OPERATION;
@@ -497,7 +497,6 @@
      */
     pEntry->setDataInfo(uncompressedLen, endPosn - startPosn, crc,
         compressionMethod);
-    modWhen = getModTime(inputFp ? fileno(inputFp) : fileno(mZipFp));
     pEntry->setModWhen(modWhen);
     pEntry->setLFHOffset(lfhPosn);
     mEOCD.mNumEntries++;