Android: Add chrome-specific dynamic linker.

content/public/android/java/templates/NativeLibraries.template

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.content.app;
 
 public class NativeLibraries {
+    // Set to true to enable the use of the Chrome Linker.
+#if defined(ENABLE_CRAZY_LINKER)
+    public static boolean USE_CRAZY_LINKER = true;

[bulach, 2013/09/09 16:14:15]

nit: final

[digit1, 2013/09/10 09:23:30]

Ah, this is _really_ subtle, this can't get final because it is part of content,
which can be used by several content-based APKs (e.g. content shell, chromium
test shell, chrome, etc...).

The point is that, during the build, this is part of content.jar, but we want to
decide in the final APK target whether to enable this or not.

There is an ugly trick performed in our build system (not invented here, it's
already necessary to handle the list of native libraries to load):

- When building the intermediate content.jar, the NativeLibraries.class file is
removed from the .jar
- Another version of NativeLibraries.class is generated for the given final
target, e.g. goes into content_shell.jar
- When generating the final .dex files, the stripped content.jar + new
content_shell.jar are linked
  together into a single .dex file.

The problem is that if the variable is final, it will be optimized out at
compile time when generating content.jar and will be either disabled / enabled
for all projects using the same intermediate file.

This issue already exists for the list of native libraries defined just below.
So we just reused the system.
I'll add a comment here.

+#else
+    public static boolean USE_CRAZY_LINKER = false;
+#endif
+
     // This is the list of native libraries to be loaded (in the correct order)
     // by LibraryLoader.java.  The content java library is compiled with no
     // array defined, and then the build system creates a version of the file
     // with the real list of libraries required (which changes based upon which
     // .apk is being built).
     // TODO(cjhopman): This is public since it is referenced by ChromeNativeTestActivity.java
     // directly. The two ways of library loading should be refactored into one.
     public static String[] libraries
 #include <native_libraries_array.h>
       ;
 }