Revert "speed up loading of toc for epub by not resolving toc url destiantion to a page, which requires layout of everything" (fixes #5514)

This reverts commit 57b4a8d.

Author: kjk

src/EngineMupdf.cpp

@@ -171,6 +171,13 @@ static int ResolveLink(fz_context* ctx, fz_document* doc, const char* uri, float
     return pageNo + 1;
 }
 
+static int FzGetPageNo(fz_context* ctx, fz_document* doc, fz_link* link, fz_outline* outline) {
+    float x, y;
+    const char* uri = link ? link->uri : outline ? outline->uri : nullptr;
+    int pageNo = ResolveLink(ctx, doc, uri, &x, &y);
+    return pageNo;
+}
+
 static IPageDestination* NewPageDestinationMupdf(fz_context* ctx, fz_document* doc, fz_link* link,
                                                  fz_outline* outline) {
     ReportIf(link && outline);
@@ -218,7 +225,7 @@ static IPageDestination* NewPageDestinationMupdf(fz_context* ctx, fz_document* d
 
     auto dest = new PageDestinationMupdf(link, outline);
     dest->rect = FzGetRectF(link, outline);
-    // pageNo is resolved lazily in HandleLinkMupdf when navigating
+    dest->pageNo = FzGetPageNo(ctx, doc, link, outline);
     return dest;
 }
 
@@ -2492,6 +2499,8 @@ TocItem* EngineMupdf::BuildTocTree(TocItem* parent, fz_outline* outline, int& id
             name = str::Dup("");
         }
 
+        int pageNo = FzGetPageNo(ctx, _doc, nullptr, outline);
+
         IPageDestination* dest = nullptr;
         if (isAttachment) {
             dest = DestFromAttachment(this, outline);
@@ -2504,8 +2513,8 @@ TocItem* EngineMupdf::BuildTocTree(TocItem* parent, fz_outline* outline, int& id
         item->isOpenDefault = outline->is_open;
         item->id = ++idCounter;
         item->fontFlags = 0; // TODO: had outline->flags; but mupdf changed outline
-        // pageNo is resolved lazily in HandleLinkMupdf when navigating
-        item->pageNo = 0;
+        item->pageNo = pageNo;
+        ReportIf(!isAttachment && !item->PageNumbersMatch());
 
         // TODO: had outline->n_color and outline->color but mupdf changed outline
         /*