Merge branch 'stable-3.1' into stable-3.2

* stable-3.1:
  PrologOptions: Enable error logging for dryrun options when debug is enabled
  config-project-config.txt: reformat submit-section
  TestSubmitType: Enable logErrors when debug logging is enabled
  TestSubmitRule: Enable logErrors when debug logging is enabled
  Fix typos in test.submit_rule and test.submit_type examples
  RestApiServlet: Log JSON parse error at debug level

Change-Id: I7bd6bf5f4fd26b5853b8c1594d39ed7e7f51a223

Documentation/config-project-config.txt

@@ -316,27 +316,35 @@ the parent project.
 The submit section includes configuration of project-specific
 submit settings:
 
-[[content_merge]]
-- 'mergeContent': Defines whether Gerrit will try to
+[[content_merge]]submit.mergeContent::
++
+Defines whether Gerrit will try to
 do a content merge when a path conflict occurs. Valid values are
 'true', 'false', or 'INHERIT'.  Default is 'INHERIT'. This option can
 be modified by any project owner through the project console, `Browse`
 > `Repositories` > my/project > `Allow content merges`.
 
-- 'action': Defines the link:#submit-type[submit type].  Valid
+[[submit.action]]submit.action::
++
+Defines the link:#submit-type[submit type].  Valid
 values are 'fast forward only', 'merge if necessary', 'rebase if necessary',
 'rebase always', 'merge always' and 'cherry pick'.  The default is 'merge if necessary'.
 
-- 'matchAuthorToCommitterDate': Defines whether to the author date will be changed to match the
-submitter date upon submit, so that git log shows when the change was submitted instead of when the
-author last committed. Valid values are 'true', 'false', or 'INHERIT'. The default is 'INHERIT'.
-This option only takes effect in submit strategies which already modify the commit, i.e.
-Cherry Pick, Rebase Always, and (perhaps) Rebase If Necessary.
+[[submit.matchAuthorToCommitterDate]]submit.matchAuthorToCommitterDate::
++
+Defines whether the author date will be changed to match the submitter date upon submit, so that
+git log shows when the change was submitted instead of when the author last committed. Valid
+values are 'true', 'false', or 'INHERIT'. The default is 'INHERIT'. This option only takes effect
+in submit strategies which already modify the commit, i.e. Cherry Pick, Rebase Always, and
+(when rebase is necessary) Rebase If Necessary.
 
-- 'rejectEmptyCommit': Defines whether empty commits should be rejected when a change is merged.
-Changes might not seem empty at first but when attempting to merge, rebasing can lead to an empty
-commit. If this option is set to 'true' the merge would fail. An empty commit is still allowed as
-the initial commit on a branch.
+[[submit.rejectEmptyCommit]]submit.rejectEmptyCommit::
++
+Defines whether empty commits should be rejected when a change is merged. When using
+link:#submit.action[submit action] Cherry Pick, Rebase If Necessary or Rebase Always changes may
+become empty upon submit, since the rebase|cherry-pick can lead to an empty commit. If this option
+is set to 'true' the merge would fail in such a case. An empty commit is still allowed as the
+initial commit on a branch.
 
 [[submit-type]]
 ==== Submit Type

Documentation/rest-api-changes.txt

@@ -4471,7 +4471,7 @@ a project-specific rule.
 .Request
 ----
   POST /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/revisions/current/test.submit_type HTTP/1.0
-  Content-Type: text/plain; charset-UTF-8
+  Content-Type: text/plain; charset=UTF-8
 
   submit_type(cherry_pick).
 ----
@@ -4502,7 +4502,7 @@ a project-specific rule.
 .Request
 ----
   POST /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/revisions/current/test.submit_rule?filters=SKIP HTTP/1.0
-  Content-Type: text/plain; charset-UTF-8
+  Content-Type: text/plain; charset=UTF-8
 
   submit_rule(submit(R)) :-
     R = label('Any-Label-Name', reject(_)).

java/com/google/gerrit/httpd/restapi/RestApiServlet.java

@@ -601,6 +601,7 @@ public class RestApiServlet extends HttpServlet {
         }
       } catch (MalformedJsonException | JsonParseException e) {
         cause = Optional.of(e);
+        logger.atFine().withCause(e).log("REST call failed on JSON parsing");
         responseBytes =
             replyError(
                 req, res, statusCode = SC_BAD_REQUEST, "Invalid " + JSON_TYPE + " in request", e);

java/com/google/gerrit/server/rules/PrologOptions.java

@@ -15,18 +15,21 @@
 package com.google.gerrit.server.rules;
 
 import com.google.auto.value.AutoValue;
+import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.common.Nullable;
 import java.util.Optional;
 
 @AutoValue
 public abstract class PrologOptions {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
   public static PrologOptions defaultOptions() {
     return new AutoValue_PrologOptions.Builder().logErrors(true).skipFilters(false).build();
   }
 
   public static PrologOptions dryRunOptions(String ruleToTest, boolean skipFilters) {
     return new AutoValue_PrologOptions.Builder()
-        .logErrors(false)
+        .logErrors(logger.atFine().isEnabled())
         .skipFilters(skipFilters)
         .rule(ruleToTest)
         .build();