Graphics: Make SurfaceTexture compile-time initializable

Ensure that all static initializer code can be executed in the
compiler. Move native field caching into the native method
registration function.

Bug: 34956610
Test: m
Test: Device boots (Pixel)
Change-Id: Icf68c8fbadcaaa133a152942a3a7ba7aba84a1df

core/jni/android/graphics/SurfaceTexture.cpp

@@ -34,6 +34,7 @@
 
 #include "jni.h"
 #include "JNIHelp.h"
+#include "ScopedLocalRef.h"
 
 // ----------------------------------------------------------------------------
 
@@ -385,7 +386,6 @@ static jboolean SurfaceTexture_isReleased(JNIEnv* env, jobject thiz)
 // ----------------------------------------------------------------------------
 
 static const JNINativeMethod gSurfaceTextureMethods[] = {
-    {"nativeClassInit",            "()V",   (void*)SurfaceTexture_classInit },
     {"nativeInit",                 "(ZIZLjava/lang/ref/WeakReference;)V", (void*)SurfaceTexture_init },
     {"nativeFinalize",             "()V",   (void*)SurfaceTexture_finalize },
     {"nativeSetDefaultBufferSize", "(II)V", (void*)SurfaceTexture_setDefaultBufferSize },
@@ -401,6 +401,10 @@ static const JNINativeMethod gSurfaceTextureMethods[] = {
 
 int register_android_graphics_SurfaceTexture(JNIEnv* env)
 {
+    // Cache some fields.
+    ScopedLocalRef<jclass> klass(env, FindClassOrDie(env, kSurfaceTextureClassPathName));
+    SurfaceTexture_classInit(env, klass.get());
+
     return RegisterMethodsOrDie(env, kSurfaceTextureClassPathName, gSurfaceTextureMethods,
                                 NELEM(gSurfaceTextureMethods));
 }

graphics/java/android/graphics/SurfaceTexture.java

@@ -403,11 +403,4 @@ public class SurfaceTexture {
     private native int nativeGetQueuedCount();
     private native void nativeRelease();
     private native boolean nativeIsReleased();
-
-    /*
-     * We use a class initializer to allow the native code to cache some
-     * field offsets.
-     */
-    private static native void nativeClassInit();
-    static { nativeClassInit(); }
 }