Android WebView: use the system ashmem.

third_party/ashmem/ashmem.gyp

Index: third_party/ashmem/ashmem.gyp
diff --git a/third_party/ashmem/ashmem.gyp b/third_party/ashmem/ashmem.gyp
index 36e231f268b0245557785e3bb9a57ebd3041a484..82e893a9cd7bb90054584d57311597bfcd9a8932 100644
--- a/third_party/ashmem/ashmem.gyp
+++ b/third_party/ashmem/ashmem.gyp
@@ -6,10 +6,28 @@
   'targets': [
     {
       'target_name': 'ashmem',
-      'type': 'static_library',
-      'sources': [
-          'ashmem.h',
-          'ashmem-dev.c'
+      'conditions': [
+        ['android_webview_build==1', {
+          # WebView must use the Android system version of ashmem to avoid
+          # linking problems.
+          'type': 'none',
+          'variables': {
+            'headers_root_path': '.',
+            'header_filenames': [ 'ashmem.h' ],
+            'shim_generator_additional_args': [
+              '--prefix', 'cutils/',
+            ],
+          },
+          'includes': [
+            '../../build/shim_headers.gypi',
+          ],
+        }, {
+          'type': 'static_library',
+          'sources': [
+            'ashmem.h',
+            'ashmem-dev.c'
+          ],
+        }],
       ],
     },
   ],