Update UI strings based on the latest user research.

chrome/android/java/strings/android_chrome_strings.grd

Index: chrome/android/java/strings/android_chrome_strings.grd
diff --git a/chrome/android/java/strings/android_chrome_strings.grd b/chrome/android/java/strings/android_chrome_strings.grd
index 68759051e22516e54b3ccb9b7f40c149f62f8ad2..cd9003454578ccef5295c8e1338dc334695d9cd8 100644
--- a/chrome/android/java/strings/android_chrome_strings.grd
+++ b/chrome/android/java/strings/android_chrome_strings.grd
@@ -1588,17 +1588,24 @@ To obtain new licenses, connect to the internet and play your downloaded content
       <message name="IDS_TRANSLATE_NEVER_TRANSLATE_LANGUAGE" desc="Text that appears on a button. Chrome asks the user if they want to translate a page from the source language into another, target language that the user may have shown interest in before. User can click the 'Never Translate' button to indicate that they never want Chrome to translate pages in this language. Imperative. [CHAR-LIMIT=64]">
         Never translate <ph name="LANGUAGE">%1$s<ex>French</ex></ph>
       </message>
-      <message name="IDS_TRANSLATE_INFOBAR_MORE_LANGUAGE" desc="Option in the Chrome menu. Lets the user open a dialog to choose other target languages for translation, from a list of available languages. [CHAR-LIMIT=64]">
+
+      <message name="IDS_TRANSLATE_OPTION_ALWAYS_TRANSLATE" desc="Option in the Chrome menu. User can click the 'Always Translate' option to indicate that they want Chrome to translate pages in this language automatically. Imperative.">
+        Always translate pages in <ph name="SOURCE_LANGUAGE">%1$s<ex>French</ex></ph>
+      </message>
+      <message name="IDS_TRANSLATE_OPTION_NEVER_TRANSLATE" desc="Option in the Chrome menu. User can click the 'Never Translate' option to indicate that they never want Chrome to translate pages in this language. The variable SOURCE_LANGUAGE could be any of 50+ languages supported by Google Translate, like French, Spanish, German, Italian, Japanese, Korean, etc. Imperative.">
+        Never translate pages in <ph name="SOURCE_LANGUAGE">%1$s<ex>French</ex></ph>
+      </message>
+      <message name="IDS_TRANSLATE_OPTION_MORE_LANGUAGE" desc="Option in the Chrome menu. Lets the user open a dialog to choose other target languages for translation, from a list of available languages. [CHAR-LIMIT=64]">
         More languages
       </message>
-      <message name="IDS_TRANSLATE_INFOBAR_NOT_SOURCE_LANGUAGE" desc="Option in the Chrome menu. Lets the user select another language as source language to translate. [CHAR-LIMIT=64]">
-        Page is not in <ph name="LANGUAGE">%1$s<ex>French</ex></ph>
+      <message name="IDS_TRANSLATE_OPTION_NOT_SOURCE_LANGUAGE" desc="Option in the Chrome menu. Sometimes a web page's source language is not correctly identified by Google Translate, and this menu option lets the user open a submenu to select another language as the source language to translate. Phrased as a question as if to query the user, 'Is this page not in [source language identified]? If so, click here.' [CHAR-LIMIT=64]">
+        Page is not in <ph name="LANGUAGE">%1$s<ex>French</ex></ph>?
       </message>
-      <message name="IDS_TRANSLATE_SNACKBAR_ALWAYS_TRANSLATE" desc="Text to be displayed in translate snackbar that lets the user know pages in this source language will be translated to target language automatically. [CHAR-LIMIT=64]">
-        Sites in <ph name="SOURCE_LANGUAGE">%1$s<ex>French</ex></ph> will be translated to <ph name="TARGET_LANGUAGE">%2$s<ex>English</ex></ph>
+      <message name="IDS_TRANSLATE_SNACKBAR_ALWAYS_TRANSLATE" desc="After the user selects 'Always translate pages in [LANGUAGE]', this text confirms the user's choice and lets them know that pages in [LANGUAGE] will be translated to their chosen target language automatically. Imperative. [CHAR-LIMIT=64]">
+        Pages in <ph name="SOURCE_LANGUAGE">%1$s<ex>French</ex></ph> will be translated to <ph name="TARGET_LANGUAGE">%2$s<ex>English</ex></ph> from now on
       </message>
-      <message name="IDS_TRANSLATE_SNACKBAR_LANGUAGE_NEVER" desc="Text to be displayed in translate snackbar that lets the user know sites in this language will not be translated. [CHAR-LIMIT=64]">
-        Sites in <ph name="LANGUAGE">%1$s<ex>French</ex></ph> will not be translated
+      <message name="IDS_TRANSLATE_SNACKBAR_LANGUAGE_NEVER" desc="After the user selects 'Never translate pages in [LANGUAGE]', this text confirms the user's choice and lets them know that pages in [LANGUAGE] will not be translated to their chosen target language automatically. Imperative[CHAR-LIMIT=64]">
+        Pages in <ph name="LANGUAGE">%1$s<ex>French</ex></ph> will not be translated
       </message>
       <message name="IDS_TRANSLATE_SNACKBAR_SITE_NEVER" desc="Text to be displayed in translate snackbar that lets the user know this site will not be translated. [CHAR-LIMIT=64]">
         This site will not be translated