Remove IPDF_TextPage, IPDF_TextPageFind and IPDF_LinkExtract interfaces.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index eede1bbd565b47db63c134b27212dee3cd6991be..63cea2eb96c1605161b8b6db3e709577bf4a814f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -479,13 +479,10 @@ static_library("fpdfapi") {
 static_library("fpdftext") {
   sources = [
     "core/fpdftext/fpdf_text_int.cpp",
-    "core/fpdftext/fpdf_text_int.h",
-    "core/fpdftext/include/ipdf_linkextract.h",
-    "core/fpdftext/include/ipdf_textpage.h",
-    "core/fpdftext/include/ipdf_textpagefind.h",
+    "core/fpdftext/include/cpdf_linkextract.h",
+    "core/fpdftext/include/cpdf_textpage.h",
+    "core/fpdftext/include/cpdf_textpagefind.h",
     "core/fpdftext/text_int.h",
-    "core/fpdftext/unicodenormalization.cpp",
-    "core/fpdftext/unicodenormalization.h",
     "core/fpdftext/unicodenormalizationdata.cpp",
     "core/fpdftext/unicodenormalizationdata.h",
   ]