Simplify the av1 extension build system

Also add cpu_features to .hgignore.

PiperOrigin-RevId: 323804458

.hgignore

@@ -65,6 +65,7 @@ extensions/vp9/src/main/jni/libyuv
 
 # AV1 extension
 extensions/av1/src/main/jni/libgav1
+extensions/av1/src/main/jni/cpu_features
 
 # Opus extension
 extensions/opus/src/main/jni/libopus

extensions/av1/README.md

@@ -39,7 +39,7 @@ git clone https://github.com/google/cpu_features
 
 ```
 cd "${AV1_EXT_PATH}/jni" && \
-git clone https://chromium.googlesource.com/codecs/libgav1 libgav1
+git clone https://chromium.googlesource.com/codecs/libgav1
 ```
 
 * Fetch Abseil:

extensions/av1/build.gradle

@@ -24,27 +24,10 @@ android {
             }
         }
     }
-
-    // This option resolves the problem of finding libgav1JNI.so
-    // on multiple paths. The first one found is picked.
-    packagingOptions {
-        pickFirst 'lib/arm64-v8a/libgav1JNI.so'
-        pickFirst 'lib/armeabi-v7a/libgav1JNI.so'
-        pickFirst 'lib/x86/libgav1JNI.so'
-        pickFirst 'lib/x86_64/libgav1JNI.so'
-    }
-
-    sourceSets.main {
-        // As native JNI library build is invoked from gradle, this is
-        // not needed. However, it exposes the built library and keeps
-        // consistency with the other extensions.
-        jniLibs.srcDir 'src/main/libs'
-    }
 }
 
-// Configure the native build only if libgav1 is present, to avoid gradle sync
-// failures if libgav1 hasn't been checked out according to the README and CMake
-// isn't installed.
+// Configure the native build only if libgav1 is present to avoid gradle sync
+// failures if libgav1 hasn't been built according to the README instructions.
 if (project.file('src/main/jni/libgav1').exists()) {
     android.externalNativeBuild.cmake.path = 'src/main/jni/CMakeLists.txt'
     android.externalNativeBuild.cmake.version = '3.7.1+'

extensions/av1/src/main/jni/CMakeLists.txt

-# libgav1JNI requires modern CMake.
 cmake_minimum_required(VERSION 3.7.1 FATAL_ERROR)
-
-# libgav1JNI requires C++11.
 set(CMAKE_CXX_STANDARD 11)
 
 project(libgav1JNI C CXX)
@@ -21,24 +18,13 @@ if(build_type MATCHES "^rel")
 endif()
 
 set(libgav1_jni_root "${CMAKE_CURRENT_SOURCE_DIR}")
-set(libgav1_jni_build "${CMAKE_BINARY_DIR}")
-set(libgav1_jni_output_directory
-    ${libgav1_jni_root}/../libs/${ANDROID_ABI}/)
-
-set(libgav1_root "${libgav1_jni_root}/libgav1")
-set(libgav1_build "${libgav1_jni_build}/libgav1")
-
-set(cpu_features_root "${libgav1_jni_root}/cpu_features")
-set(cpu_features_build "${libgav1_jni_build}/cpu_features")
 
 # Build cpu_features library.
-add_subdirectory("${cpu_features_root}"
-                 "${cpu_features_build}"
+add_subdirectory("${libgav1_jni_root}/cpu_features"
                  EXCLUDE_FROM_ALL)
 
 # Build libgav1.
-add_subdirectory("${libgav1_root}"
-                 "${libgav1_build}"
+add_subdirectory("${libgav1_jni_root}/libgav1"
                  EXCLUDE_FROM_ALL)
 
 # Build libgav1JNI.
@@ -58,7 +44,3 @@ target_link_libraries(gav1JNI
                       PRIVATE libgav1_static
                       PRIVATE ${android_log_lib})
 
-# Specify output directory for libgav1JNI.
-set_target_properties(gav1JNI PROPERTIES
-                      LIBRARY_OUTPUT_DIRECTORY
-                      ${libgav1_jni_output_directory})