Selectively perform JNI registration in render processes on Android.

chrome/browser/android/chrome_entry_point.cc

Index: chrome/browser/android/chrome_entry_point.cc
diff --git a/chrome/browser/android/chrome_entry_point.cc b/chrome/browser/android/chrome_entry_point.cc
index 5bc9215ded3a07c1f0967cfd1f5461d7ffd50081..4a540518ea52b1de61bebefb9d50edf12251fa6c 100644
--- a/chrome/browser/android/chrome_entry_point.cc
+++ b/chrome/browser/android/chrome_entry_point.cc
@@ -3,6 +3,7 @@
 // found in the LICENSE file.
 
 #include "base/android/jni_android.h"
+#include "base/android/jni_utils.h"
 #include "base/android/library_loader/library_loader_hooks.h"
 #include "base/bind.h"
 #include "chrome/app/android/chrome_jni_onload.h"
@@ -25,6 +26,15 @@ bool NativeInit() {
 
 // This is called by the VM when the shared library is first loaded.
 JNI_EXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+  // By default, all JNI methods are registered. However, since render processes
+  // don't need very much Java code, we enable selective JNI registration on the
+  // Java side and only register a subset of JNI methods.
+  base::android::InitVM(vm);
+  JNIEnv* env = base::android::AttachCurrentThread();
+  if (base::android::isSelectiveJniRegistrationEnabled(env)) {
+    base::android::SetJniRegistrationType(
+        base::android::SELECTIVE_JNI_REGISTRATION);
+  }
   if (!android::OnJNIOnLoadRegisterJNI(vm, base::Bind(&RegisterJNI))) {
     return -1;
   }