Enable video in linux build and remove unneeded ifdefs to guard windows.

media/base/media_posix.cc

Index: media/base/media_posix.cc
diff --git a/media/base/media_posix.cc b/media/base/media_posix.cc
index edbced068acb2cd0ba52218617b7186c2aef7dff..1b3f323e084fc5ebd0b27cb0efdc5b56a685fe37 100644
--- a/media/base/media_posix.cc
+++ b/media/base/media_posix.cc
@@ -22,11 +22,6 @@
 // be promising, but I don't quite understand it yet.
 extern "C" {
 
-int (*av_get_bits_per_sample_format_ptr)(enum SampleFormat sample_fmt);
-int av_get_bits_per_sample_format(enum SampleFormat sample_fmt) {
-  return av_get_bits_per_sample_format(sample_fmt);
-}
-
 void (*avcodec_init_ptr)(void) = NULL;
 void avcodec_init(void) {
   avcodec_init_ptr();
@@ -75,6 +70,11 @@ int avcodec_decode_video(AVCodecContext* avctx, AVFrame* picture,
 }
 
 
+int (*av_get_bits_per_sample_format_ptr)(enum SampleFormat sample_fmt);
+int av_get_bits_per_sample_format(enum SampleFormat sample_fmt) {
+  return av_get_bits_per_sample_format_ptr(sample_fmt);
+}
+
 void (*av_register_all_ptr)(void);
 void av_register_all(void) {
   av_register_all_ptr();
@@ -99,12 +99,29 @@ int av_read_frame(AVFormatContext* s, AVPacket* pkt) {
   return av_read_frame_ptr(s, pkt);
 }
 
+int (*av_seek_frame_ptr)(AVFormatContext* s, int stream_index,
+                         int64_t timestamp, int flags) = NULL;
+int av_seek_frame(AVFormatContext* s, int stream_index,
+                  int64_t timestamp, int flags) {
+  return av_seek_frame_ptr(s, stream_index, timestamp, flags);
+}
+
+int (*av_register_protocol_ptr)(URLProtocol* protocol) = NULL;
+int av_register_protocol(URLProtocol* protocol) {
+  return av_register_protocol_ptr(protocol);
+}
+
 
 void* (*av_malloc_ptr)(unsigned int size) = NULL;
 void* av_malloc(unsigned int size) {
   return av_malloc_ptr(size);
 }
 
+void (*av_free_ptr)(void* ptr) = NULL;
+void av_free(void* ptr) {
+  return av_free_ptr(ptr);
+}
+
 }  // extern "C"
 
 
@@ -169,9 +186,6 @@ bool InitializeMediaLibrary(const FilePath& module_dir) {
   // TODO(ajwong): Extract this to somewhere saner, and hopefully
   // autogenerate the bindings from the .def files.  Having all this
   // code here is incredibly ugly.
-  av_get_bits_per_sample_format_ptr =
-      reinterpret_cast<int (*)(enum SampleFormat)>(
-          dlsym(libs[FILE_LIBAVCODEC], "av_get_bits_per_sample_format"));
   avcodec_init_ptr =
       reinterpret_cast<void(*)(void)>(
           dlsym(libs[FILE_LIBAVCODEC], "avcodec_init"));
@@ -196,6 +210,9 @@ bool InitializeMediaLibrary(const FilePath& module_dir) {
                                const uint8_t*, int)>(
           dlsym(libs[FILE_LIBAVCODEC], "avcodec_decode_video"));
 
+  av_get_bits_per_sample_format_ptr =
+      reinterpret_cast<int (*)(enum SampleFormat)>(
+          dlsym(libs[FILE_LIBAVCODEC], "av_get_bits_per_sample_format"));
   av_register_all_ptr =
       reinterpret_cast<void(*)(void)>(
           dlsym(libs[FILE_LIBAVFORMAT], "av_register_all"));
@@ -210,10 +227,19 @@ bool InitializeMediaLibrary(const FilePath& module_dir) {
   av_read_frame_ptr =
       reinterpret_cast<int (*)(AVFormatContext*, AVPacket*)>(
           dlsym(libs[FILE_LIBAVFORMAT], "av_read_frame"));
+  av_seek_frame_ptr =
+      reinterpret_cast<int (*)(AVFormatContext*, int, int64_t, int)>(
+          dlsym(libs[FILE_LIBAVFORMAT], "av_seek_frame"));
+  av_register_protocol_ptr =
+      reinterpret_cast<int (*)(URLProtocol*)>(
+          dlsym(libs[FILE_LIBAVFORMAT], "av_register_protocol"));
 
   av_malloc_ptr =
       reinterpret_cast<void* (*)(unsigned int)>(
           dlsym(libs[FILE_LIBAVUTIL], "av_malloc"));
+  av_free_ptr =
+      reinterpret_cast<void (*)(void*)>(
+          dlsym(libs[FILE_LIBAVUTIL], "av_free"));
 
   // Check that all the symbols were loaded correctly before returning true.
   if (avcodec_init_ptr &&
@@ -224,11 +250,15 @@ bool InitializeMediaLibrary(const FilePath& module_dir) {
       avcodec_decode_audio2_ptr &&
       avcodec_decode_video_ptr &&
 
+      av_get_bits_per_sample_format_ptr &&
       av_register_all_ptr &&
       av_open_input_file_ptr &&
       av_find_stream_info_ptr &&
       av_read_frame_ptr &&
+      av_seek_frame_ptr &&
+      av_register_protocol_ptr &&
 
+      av_free_ptr &&
       av_malloc_ptr) {
     return true;
   }