MPEG4Source: fix fragmented read.

Test: passed CTS test DecoderTest#testDecodeFragmented
Bug: 64314728
Bug: 36571704
Change-Id: I71ad6aaae473b03483f8405899d3178148597bba
(cherry picked from commit ba9af7792dfed6e9b1b216aab91a97e713eec891)
(cherry picked from commit 6b401a337674f2f22b7589534700a33187899869)

media/libstagefright/MPEG4Extractor.cpp

diff --git a/media/libstagefright/MPEG4Extractor.cpp b/media/libstagefright/MPEG4Extractor.cpp
index 1dfa868..2cc43c1 100644
--- a/media/libstagefright/MPEG4Extractor.cpp
+++ b/media/libstagefright/MPEG4Extractor.cpp
@@ -3795,7 +3795,8 @@
 
                 while (true) {
                     if (mDataSource->readAt(*offset, hdr, 8) < 8) {
-                        return ERROR_END_OF_STREAM;
+                        // no more box to the end of file.
+                        break;
                     }
                     chunk_size = ntohl(hdr[0]);
                     chunk_type = ntohl(hdr[1]);