android: Add the Chromium linker library to Trichrome ARM64.

It wasn't present in the ARM64 builds, update the build files to fix this.
Tested with 'target_cpu = "arm64"'.

Bug: 1002141, 979638
Change-Id: I835efc915ce07482aadc83821b74782f921a6115
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1795443Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Commit-Queue: Benoit L <lizeb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#695146}

chrome/android/trichrome.gni

@@ -108,21 +108,29 @@ template("trichrome_library_apk_tmpl") {
     }
 
     if (android_64bit_target_cpu) {
-      # Include the actual browser-bitness libmonochrome library, and an
-      # opposite-bitness placeholder library to ensure that the library is
-      # treated as multiarch and gets its Java code precompiled for both
-      # architectures.
+      # Include the actual browser-bitness libmonochrome library, dependencies
+      # (crashpad and linker), and an opposite-bitness placeholder library to
+      # ensure that the library is treated as multiarch and gets its Java code
+      # precompiled for both architectures.
       native_lib_placeholders = [ "libdummy.so" ]
       if (build_apk_secondary_abi) {
         secondary_abi_shared_libraries =
             [ "//chrome/android:monochrome_secondary_abi_lib" ]
 
         _trampoline = "//third_party/crashpad/crashpad/handler:crashpad_handler_trampoline($android_secondary_abi_toolchain)"
+
         deps += [ _trampoline ]
         _secondary_out_dir = get_label_info(_trampoline, "root_out_dir")
         secondary_abi_loadable_modules =
             [ "$_secondary_out_dir/libcrashpad_handler_trampoline.so" ]
       }
+
+      if (use_chromium_linker) {
+        deps += [ "//base/android/linker:chromium_android_linker($android_secondary_abi_toolchain)" ]
+        secondary_abi_loadable_modules +=
+            [ "$_secondary_out_dir/libchromium_android_linker.so" ]
+      }
+
       if (trichrome_shared_assets) {
         deps += [ "//android_webview:v8_snapshot_secondary_abi_assets" ]
       }