[MSKP] update Android MSKP capture documentation

Change-Id: I8294f76ac91bd2fc303b3c9e5e012858740008e8
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/969216
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Jorge Betancourt <jmbetancourt@google.com>

site/docs/dev/tools/android-capture.md

diff --git a/site/docs/dev/tools/android-capture.md b/site/docs/dev/tools/android-capture.md
index c6d78d8..b4c138c 100644
--- a/site/docs/dev/tools/android-capture.md
+++ b/site/docs/dev/tools/android-capture.md
@@ -37,11 +37,12 @@
 https://source.android.com/docs/setup/download.)
 
 ```
-frameworks/base/libs/hwui/tests/scripts/skp-capture.sh PACKAGE_NAME FRAMES
+frameworks/base/libs/hwui/tests/scripts/skp-capture.sh -p PACKAGE_NAME -n FRAMES
 ```
 
 `PACKAGE_NAME` is the name of the component or app you want to capture, for
-example: **com.google.android.apps.nexuslauncher**.
+example: **com.google.android.apps.nexuslauncher**. If not specified, the script will attempt
+to infer the package name of the currently open application.
 
 `FRAMES` is the number of frames to capture. This is optional and defaults to 1.