Selectively perform JNI registration in render processes on Android.

base/android/java/src/org/chromium/base/CpuFeatures.java

Index: base/android/java/src/org/chromium/base/CpuFeatures.java
diff --git a/base/android/java/src/org/chromium/base/CpuFeatures.java b/base/android/java/src/org/chromium/base/CpuFeatures.java
index ae4969c99ea0ecc70a9454987e0b871e9140f171..afd16a0fa4a2f77c4d628f7f60b065e7f2b6ecf7 100644
--- a/base/android/java/src/org/chromium/base/CpuFeatures.java
+++ b/base/android/java/src/org/chromium/base/CpuFeatures.java
@@ -5,6 +5,7 @@
 package org.chromium.base;
 
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.base.annotations.MainDex;
 
 // The only purpose of this class is to allow sending CPU properties
 // from the browser process to sandboxed renderer processes. This is
@@ -20,6 +21,7 @@ import org.chromium.base.annotations.JNINamespace;
 // there is no point in duplicating their definitions here.
 //
 @JNINamespace("base::android")
+@MainDex // Used by child processes in tests.
 public abstract class CpuFeatures {
     /**
      * Return the number of CPU Cores on the device.