[media] Set allocation limit compatible with FFmpeg 4.3

Previously we set the limit to zero, meaning no limit, but FFmpeg 4.3
will not allocate at all with that setting.

Changed to std::numeric_limits<size_t>::max().

Bug: 1095962
Change-Id: I96820c21f794f2814e955ee75ff22dfd31804c29
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2349405Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Dan Sanders <sandersd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#796966}

media/base/media.cc

@@ -4,6 +4,9 @@
 
 #include "media/base/media.h"
 
+#include <stdint.h>
+#include <limits>
+
 #include "base/allocator/buildflags.h"
 #include "base/command_line.h"
 #include "base/macros.h"
@@ -41,7 +44,7 @@ class MediaInitializer {
 
 #if BUILDFLAG(USE_ALLOCATOR_SHIM)
     // Remove allocation limit from ffmpeg, so calls go down to shim layer.
-    av_max_alloc(0);
+    av_max_alloc(std::numeric_limits<size_t>::max());
 #endif  // BUILDFLAG(USE_ALLOCATOR_SHIM)
 
 #endif  // BUILDFLAG(ENABLE_FFMPEG)