[spelling] existance to existence

android_webview/test/unittest/assets/asset_file.ogg

Index: android_webview/test/unittest/assets/asset_file.ogg
diff --git a/android_webview/test/unittest/assets/asset_file.ogg b/android_webview/test/unittest/assets/asset_file.ogg
index 1e9e1a13dd94cd85cda47e64a7f2a81f4e9df26f..ab0f96738fee8ee632df19938264997359916a51 100644
--- a/android_webview/test/unittest/assets/asset_file.ogg
+++ b/android_webview/test/unittest/assets/asset_file.ogg
@@ -3,5 +3,5 @@ see android_webview_unittests_apk and AwMediaUrlInterceptorTest.
 
 This is a text file, but we use the .ogg extension so that aapt will not
 compress its contents. This is ok for the purpose of the unit tests since
-they do not play the media, and they are only interested in the existance of
+they do not play the media, and they are only interested in the existence of
 an uncompressed media file in the assets directory.