[webcodecs] Limit max frame size to 8k

8k is big enough for most practical applications and saves some
of OOMs and crashes of underlying codecs.

Bug: 1127633, 1129359
Change-Id: I619a28dd6cb4eefc38f0328ca179e2684e627826
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2417511
Commit-Queue: Eugene Zemtsov <eugene@chromium.org>
Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Cr-Commit-Position: refs/heads/master@{#808216}

third_party/blink/renderer/modules/webcodecs/video_encoder.cc

@@ -129,16 +129,19 @@ int32_t VideoEncoder::encodeQueueSize() {
 std::unique_ptr<VideoEncoder::ParsedConfig> VideoEncoder::ParseConfig(
     const VideoEncoderConfig* config,
     ExceptionState& exception_state) {
+  constexpr int kMaxSupportedFrameSize = 8000;
   auto parsed = std::make_unique<ParsedConfig>();
 
   parsed->options.height = config->height();
-  if (parsed->options.height == 0) {
+  if (parsed->options.height == 0 ||
+      parsed->options.height > kMaxSupportedFrameSize) {
     exception_state.ThrowTypeError("Invalid height.");
     return nullptr;
   }
 
   parsed->options.width = config->width();
-  if (parsed->options.width == 0) {
+  if (parsed->options.width == 0 ||
+      parsed->options.width > kMaxSupportedFrameSize) {
     exception_state.ThrowTypeError("Invalid width.");
     return nullptr;
   }