Reland "Fix search restart after zero entries (again)."

This reverts commit 735b1fdc.

Reason for revert: Speculative revert did not fix the failure

Original change's description:
> Revert "Fix search restart after zero entries (again)."
> 
> This reverts commit d41579e2.
> 
> Reason for revert: Speculative revert.
> This is the only CL in https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/chromeos-kevin-rel/325 when it started to break.
> 
> Original change's description:
> > Fix search restart after zero entries (again).
> > 
> > The fix was lost in refactoring that ended up duplicating
> > the last_find_request_completed_with_no_matches_ member.
> > 
> > BUG=669983
> > 
> > Change-Id: I09229496d183ef3f9b69c6089a6ac3ecd8b5ef82
> > Reviewed-on: https://chromium-review.googlesource.com/c/1477835
> > Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
> > Reviewed-by: Kentaro Hara <haraken@chromium.org>
> > Commit-Queue: Rakina Zata Amni <rakina@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#634599}
> 
> TBR=haraken@chromium.org,rakina@chromium.org,allan.jensen@qt.io
> 
> Change-Id: I5b59c759eb23e526892b8fdab7ed580306cfd6d6
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 669983
> Reviewed-on: https://chromium-review.googlesource.com/c/1482455
> Reviewed-by: Christos Froussios <cfroussios@chromium.org>
> Commit-Queue: Christos Froussios <cfroussios@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#634625}

TBR=haraken@chromium.org,cfroussios@chromium.org,rakina@chromium.org,allan.jensen@qt.io

Change-Id: Ia19ee92cf309fa3b2554c226170412c4722bcbce
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 669983
Reviewed-on: https://chromium-review.googlesource.com/c/1483079Reviewed-by: Christos Froussios <cfroussios@chromium.org>
Commit-Queue: Christos Froussios <cfroussios@chromium.org>
Cr-Commit-Position: refs/heads/master@{#634631}

third_party/blink/renderer/core/editing/finder/find_task_controller.cc

@@ -301,4 +301,8 @@ void FindTaskController::Trace(Visitor* visitor) {
   visitor->Trace(resume_finding_from_range_);
 }
 
+void FindTaskController::ResetLastFindRequestCompletedWithNoMatches() {
+  last_find_request_completed_with_no_matches_ = false;
+}
+
 }  // namespace blink

third_party/blink/renderer/core/editing/finder/find_task_controller.h

@@ -76,6 +76,8 @@ class CORE_EXPORT FindTaskController final
 
   void Trace(Visitor* visitor);
 
+  void ResetLastFindRequestCompletedWithNoMatches();
+
  private:
   void RequestIdleFindTask(int identifier,
                            const WebString& search_text,

third_party/blink/renderer/core/editing/finder/text_finder.cc

@@ -206,7 +206,7 @@ bool TextFinder::Find(int identifier,
   }
 
   // We found something, so the result of the previous scoping may be outdated.
-  last_find_request_completed_with_no_matches_ = false;
+  find_task_controller_->ResetLastFindRequestCompletedWithNoMatches();
 
   return true;
 }
@@ -661,7 +661,6 @@ TextFinder::TextFinder(WebLocalFrameImpl& owner_frame)
       find_match_markers_version_(0),
       should_locate_active_rect_(false),
       scoping_in_progress_(false),
-      last_find_request_completed_with_no_matches_(false),
       find_match_rects_are_valid_(false) {}
 
 TextFinder::~TextFinder() = default;

third_party/blink/renderer/core/editing/finder/text_finder.h

@@ -240,10 +240,6 @@ class CORE_EXPORT TextFinder final
   // Keeps track of whether there is an scoping effort ongoing in the frame.
   bool scoping_in_progress_;
 
-  // Keeps track of whether the last find request completed its scoping effort
-  // without finding any matches in this frame.
-  bool last_find_request_completed_with_no_matches_;
-
   // Determines if the rects in the find-in-page matches cache of this frame
   // are invalid and should be recomputed.
   bool find_match_rects_are_valid_;