[Autofill Assistant] Changes initial text.

Bug: 806868
Change-Id: Ibb115c06bd38f4f5749d15a292d93206dba13d32
Reviewed-on: https://chromium-review.googlesource.com/c/1307410Reviewed-by: Stephane Zermatten <szermatt@chromium.org>
Commit-Queue: Lukasz Suder <lsuder@google.com>
Cr-Commit-Position: refs/heads/master@{#604283}

components/autofill_assistant_strings.grdp

@@ -5,7 +5,7 @@
       Service is not available. Try again later.
     </message>
     <message name="IDS_AUTOFILL_ASSISTANT_LOADING" desc="Text label that is shown during the loading of the first page, right after being triggered.">
-      Loading <ph name="SITE_NAME">$1<ex>google.com</ex></ph>…
+      Opening <ph name="SITE_NAME">$1<ex>google.com</ex></ph>…
     </message>
     <message name="IDS_AUTOFILL_ASSISTANT_PAYMENT_INFO_CONFIRM" desc="Text on the payment request primary button to confirm payment information [CHAR-LIMIT=32]" formatter_data="android_java">
       Confirm