Revert "Switch pdfium target from a static library to a component"

This reverts commit 7098d046898e25933ee5f1cea9ae1774f1ac39b2.

Reason for revert: Cannot roll into Chromium. See:

https://chromium-review.googlesource.com/c/chromium/src/+/1588908

Original change's description:
> Switch pdfium target from a static library to a component
> 
> Reduces size of build directory by 206 MiB (-1.0%) when building "all"
> with gn args "use_goma=true is_component_build=true is_debug=false
> enable_nacl=false symbol_level=1".  Build time also reduced from
> 426.111s to 405.252s, though I only took one sample.
> 
> Also added some missing dependencies that were causing linker failures
> in component builds.
> 
> BUG=chromium:941663
> R=​thestig
> 
> Change-Id: I03cfcac6206a42729139de8e93249c906b63d9a7
> Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/53290
> Commit-Queue: Lei Zhang <thestig@chromium.org>
> Reviewed-by: Lei Zhang <thestig@chromium.org>

TBR=thestig@chromium.org,thomasanderson@google.com,thomasanderson@chromium.org

Change-Id: I5481779d7f07f887b7f533eb1efd726d3ea4e4f4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:941663
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/53710
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 65a8597..83fc631 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -129,7 +129,7 @@
   public_configs = [ ":pdfium_public_config" ]
 }
 
-jumbo_component("pdfium") {
+jumbo_static_library("pdfium") {
   sources = [
     "fpdfsdk/fpdf_annot.cpp",
     "fpdfsdk/fpdf_attachment.cpp",
@@ -184,8 +184,6 @@
     "core/fxcrt",
   ]
 
-  defines = [ "FPDF_IMPLEMENTATION" ]
-
   if (pdf_enable_xfa) {
     deps += [
       "fpdfsdk/fpdfxfa",
@@ -361,7 +359,6 @@
   ]
   deps = [
     ":pdfium",
-    "core/fxcrt",
     "testing/image_diff",
     "//build/win:default_exe_manifest",
   ]
diff --git a/core/fxcrt/BUILD.gn b/core/fxcrt/BUILD.gn
index fd21666..88337ff 100644
--- a/core/fxcrt/BUILD.gn
+++ b/core/fxcrt/BUILD.gn
@@ -88,7 +88,6 @@
     "../../fpdfsdk/*",
     "../../fxbarcode:*",
     "../../fxjs:*",
-    "../../testing/fuzzers:*",
     "../../third_party:fx_agg",
     "../../third_party:fx_lcms2",
     "../../third_party:fx_tiff",
diff --git a/public/fpdfview.h b/public/fpdfview.h
index 601ac54..8892da5 100644
--- a/public/fpdfview.h
+++ b/public/fpdfview.h
@@ -154,27 +154,12 @@
 // Dictionary value types.
 typedef int FPDF_OBJECT_TYPE;
 
-#if defined(COMPONENT_BUILD)
-#if defined(WIN32)
-#if defined(FPDF_IMPLEMENTATION)
+#if defined(_WIN32) && defined(FPDFSDK_EXPORTS)
+// On Windows system, functions are exported in a DLL
 #define FPDF_EXPORT __declspec(dllexport)
-#else
-#define FPDF_EXPORT __declspec(dllimport)
-#endif  // defined(FPDF_IMPLEMENTATION)
-#else
-#if defined(FPDF_IMPLEMENTATION)
-#define FPDF_EXPORT __attribute__((visibility("default")))
-#else
-#define FPDF_EXPORT
-#endif  // defined(FPDF_IMPLEMENTATION)
-#endif  // defined(WIN32)
-#else
-#define FPDF_EXPORT
-#endif  // defined(COMPONENT_BUILD)
-
-#if defined(WIN32) && defined(FPDFSDK_EXPORTS)
 #define FPDF_CALLCONV __stdcall
 #else
+#define FPDF_EXPORT
 #define FPDF_CALLCONV
 #endif
 
diff --git a/testing/fuzzers/BUILD.gn b/testing/fuzzers/BUILD.gn
index d19dbfc..0dbbccc 100644
--- a/testing/fuzzers/BUILD.gn
+++ b/testing/fuzzers/BUILD.gn
@@ -143,7 +143,6 @@
       "pdf_fx_date_helpers_fuzzer.cc",
     ]
     deps = [
-      "../../fpdfsdk",
       "../../fxjs",
     ]
   }
@@ -346,7 +345,6 @@
   ]
   deps = [
     ":utils",
-    "../../core/fpdfapi",
     "../../core/fpdfapi/parser",
     "../../core/fxcodec",
     "../../core/fxge",
@@ -410,9 +408,6 @@
   sources = [
     "pdf_xml_fuzzer.cc",
   ]
-  deps = [
-    "../../core/fxcrt",
-  ]
 }
 
 pdfium_public_fuzzer("pdfium_fuzzer_src") {