Introduce a client minimum picture pool size

content/renderer/pepper/pepper_video_decoder_host.cc

Index: content/renderer/pepper/pepper_video_decoder_host.cc
diff --git a/content/renderer/pepper/pepper_video_decoder_host.cc b/content/renderer/pepper/pepper_video_decoder_host.cc
index 24becb5151442b7048b24262a4d88b5eba20e887..66d7d8fb9f9913e23b3e0e6877ad444b97e4f1ba 100644
--- a/content/renderer/pepper/pepper_video_decoder_host.cc
+++ b/content/renderer/pepper/pepper_video_decoder_host.cc
@@ -13,6 +13,7 @@
 #include "content/renderer/pepper/gfx_conversion.h"
 #include "content/renderer/pepper/ppb_graphics_3d_impl.h"
 #include "content/renderer/pepper/video_decoder_shim.h"
+#include "media/base/limits.h"
 #include "media/video/video_decode_accelerator.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/pp_errors.h"
@@ -81,6 +82,7 @@ PepperVideoDecoderHost::PepperVideoDecoderHost(RendererPpapiHost* host,
                                                PP_Resource resource)
     : ResourceHost(host->GetPpapiHost(), instance, resource),
       renderer_ppapi_host_(host),
+      min_picture_count_(0),
       initialized_(false) {
 }
 
@@ -113,7 +115,8 @@ int32_t PepperVideoDecoderHost::OnHostMsgInitialize(
     ppapi::host::HostMessageContext* context,
     const ppapi::HostResource& graphics_context,
     PP_VideoProfile profile,
-    PP_HardwareAcceleration acceleration) {
+    PP_HardwareAcceleration acceleration,
+    uint32_t min_picture_count) {
   if (initialized_)
     return PP_ERROR_FAILED;
 
@@ -130,13 +133,16 @@ int32_t PepperVideoDecoderHost::OnHostMsgInitialize(
 
   media::VideoCodecProfile media_profile = PepperToMediaVideoProfile(profile);
 
+  min_picture_count_ = min_picture_count;
+
   if (acceleration != PP_HARDWAREACCELERATION_NONE) {
     // This is not synchronous, but subsequent IPC messages will be buffered, so
     // it is okay to immediately send IPC messages through the returned channel.
     GpuChannelHost* channel = graphics3d->channel();
     DCHECK(channel);
     decoder_ = channel->CreateVideoDecoder(command_buffer_route_id);
-    if (decoder_ && decoder_->Initialize(media_profile, this)) {
+    if (decoder_ &&
+        decoder_->Initialize(media_profile, this)) {
       initialized_ = true;
       return PP_OK;
     }
@@ -148,7 +154,10 @@ int32_t PepperVideoDecoderHost::OnHostMsgInitialize(
 #if defined(OS_ANDROID)
   return PP_ERROR_NOTSUPPORTED;
 #else
-  decoder_.reset(new VideoDecoderShim(this));
+  uint32_t shim_texture_pool_size = media::limits::kMaxVideoFrames + 1;
+  shim_texture_pool_size = std::max(shim_texture_pool_size,
+                                    min_picture_count_);
+  decoder_.reset(new VideoDecoderShim(this, shim_texture_pool_size));
   initialize_reply_context_ = context->MakeReplyMessageContext();
   decoder_->Initialize(media_profile, this);
 
@@ -319,7 +328,7 @@ void PepperVideoDecoderHost::ProvidePictureBuffers(
     uint32 requested_num_of_buffers,
     const gfx::Size& dimensions,
     uint32 texture_target) {
-  RequestTextures(requested_num_of_buffers,
+  RequestTextures(std::max(min_picture_count_, requested_num_of_buffers),
                   dimensions,
                   texture_target,
                   std::vector<gpu::Mailbox>());