Migrate GetCenteredPageContentRect() out of PrintedDocument

The Windows-only PrintedDocument::GetCenteredPageContentRect() function
doesn't require any PrintedDocument internals.  This can be moved to
the printing utilities.

This relocation is part of the PrintedDocument refactoring to remove
system printing calls from its implementations.  Placing it in the
utility location will assist in the forthcoming refactoring of
PrintedDocument::RenderPrintedPage() in https://crrev.com/c/3183193.

There is no change to the functionality of GetCenteredPageContentRect()
with this move.

Bug: 809738
Change-Id: I80aaf066721e1abc504cf566606dc7c4fd9ca6df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3183046
Commit-Queue: Alan Screen <awscreen@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#947595}

printing/BUILD.gn

@@ -361,7 +361,6 @@ test("printing_unittests") {
   if (is_win) {
     sources += [
       "emf_win_unittest.cc",
-      "printed_document_unittest.cc",
       "printed_page_win_unittest.cc",
       "printing_context_win_unittest.cc",
     ]

printing/printed_document.cc

@@ -277,25 +277,6 @@ void PrintedDocument::DebugDumpData(
                      base::RetainedRef(data)));
 }
 
-#if defined(OS_WIN)
-// static
-gfx::Rect PrintedDocument::GetCenteredPageContentRect(
-    const gfx::Size& paper_size,
-    const gfx::Size& page_size,
-    const gfx::Rect& page_content_rect) {
-  gfx::Rect content_rect = page_content_rect;
-  if (paper_size.width() > page_size.width()) {
-    int diff = paper_size.width() - page_size.width();
-    content_rect.set_x(content_rect.x() + diff / 2);
-  }
-  if (paper_size.height() > page_size.height()) {
-    int diff = paper_size.height() - page_size.height();
-    content_rect.set_y(content_rect.y() + diff / 2);
-  }
-  return content_rect;
-}
-#endif
-
 PrintedDocument::Mutable::Mutable() = default;
 
 PrintedDocument::Mutable::~Mutable() = default;

printing/printed_document.h

@@ -125,14 +125,6 @@ class COMPONENT_EXPORT(PRINTING) PrintedDocument
       const std::u16string& document_name,
       const base::FilePath::StringType& extension);
 
-#if defined(OS_WIN)
-  // Get page content rect adjusted based on
-  // http://dev.w3.org/csswg/css3-page/#positioning-page-box
-  static gfx::Rect GetCenteredPageContentRect(const gfx::Size& paper_size,
-                                              const gfx::Size& page_size,
-                                              const gfx::Rect& content_rect);
-#endif
-
   // Dump data on blocking task runner.
   // Should only be called when debug dumps are enabled.
   void DebugDumpData(const base::RefCountedMemory* data,

printing/printed_document_win.cc

@@ -10,6 +10,7 @@
 #include "printing/page_number.h"
 #include "printing/printed_page_win.h"
 #include "printing/printing_context_win.h"
+#include "printing/printing_utils.h"
 #include "printing/units.h"
 #include "skia/ext/skia_utils_win.h"
 

printing/printing_utils.cc

@@ -14,6 +14,7 @@
 #include "base/strings/string_piece.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
+#include "build/build_config.h"
 #include "printing/units.h"
 #include "third_party/icu/source/common/unicode/uchar.h"
 #include "ui/gfx/geometry/size.h"
@@ -106,4 +107,21 @@ bool SizesEqualWithinEpsilon(const gfx::Size& lhs,
          std::abs(lhs.height() - rhs.height()) <= epsilon;
 }
 
+#if defined(OS_WIN)
+gfx::Rect GetCenteredPageContentRect(const gfx::Size& paper_size,
+                                     const gfx::Size& page_size,
+                                     const gfx::Rect& page_content_rect) {
+  gfx::Rect content_rect = page_content_rect;
+  if (paper_size.width() > page_size.width()) {
+    int diff = paper_size.width() - page_size.width();
+    content_rect.set_x(content_rect.x() + diff / 2);
+  }
+  if (paper_size.height() > page_size.height()) {
+    int diff = paper_size.height() - page_size.height();
+    content_rect.set_y(content_rect.y() + diff / 2);
+  }
+  return content_rect;
+}
+#endif  // defined(OS_WIN)
+
 }  // namespace printing

printing/printing_utils.h

@@ -11,6 +11,11 @@
 
 #include "base/component_export.h"
 #include "base/strings/string_piece.h"
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include "ui/gfx/geometry/rect.h"
+#endif
 
 namespace gfx {
 class Size;
@@ -48,6 +53,15 @@ bool SizesEqualWithinEpsilon(const gfx::Size& lhs,
                              const gfx::Size& rhs,
                              int epsilon);
 
+#if defined(OS_WIN)
+// Get page content rect adjusted based on
+// http://dev.w3.org/csswg/css3-page/#positioning-page-box
+COMPONENT_EXPORT(PRINTING_BASE)
+gfx::Rect GetCenteredPageContentRect(const gfx::Size& paper_size,
+                                     const gfx::Size& page_size,
+                                     const gfx::Rect& page_content_rect);
+#endif
+
 }  // namespace printing
 
 #endif  // PRINTING_PRINTING_UTILS_H_

printing/printing_utils_unittest.cc

@@ -10,9 +10,14 @@
 #include <string>
 
 #include "base/strings/utf_string_conversions.h"
+#include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/geometry/size.h"
 
+#if defined(OS_WIN)
+#include "ui/gfx/geometry/rect.h"
+#endif
+
 namespace printing {
 
 namespace {
@@ -99,4 +104,47 @@ TEST(PrintingUtilsTest, SizesEqualWithinEpsilon) {
       SizesEqualWithinEpsilon(kIsoA4Microns, gfx::Size(210500, 296500), 500));
 }
 
+#if defined(OS_WIN)
+TEST(PrintingUtilsTest, GetCenteredPageContentRect) {
+  gfx::Rect page_content;
+
+  // No centering.
+  gfx::Size page_size = gfx::Size(1200, 1200);
+  gfx::Rect page_content_rect = gfx::Rect(0, 0, 400, 1100);
+  page_content = GetCenteredPageContentRect(gfx::Size(1000, 1000), page_size,
+                                            page_content_rect);
+  EXPECT_EQ(0, page_content.x());
+  EXPECT_EQ(0, page_content.y());
+  EXPECT_EQ(400, page_content.width());
+  EXPECT_EQ(1100, page_content.height());
+
+  // X centered.
+  page_size = gfx::Size(500, 1200);
+  page_content = GetCenteredPageContentRect(gfx::Size(1000, 1000), page_size,
+                                            page_content_rect);
+  EXPECT_EQ(250, page_content.x());
+  EXPECT_EQ(0, page_content.y());
+  EXPECT_EQ(400, page_content.width());
+  EXPECT_EQ(1100, page_content.height());
+
+  // Y centered.
+  page_size = gfx::Size(1200, 500);
+  page_content = GetCenteredPageContentRect(gfx::Size(1000, 1000), page_size,
+                                            page_content_rect);
+  EXPECT_EQ(0, page_content.x());
+  EXPECT_EQ(250, page_content.y());
+  EXPECT_EQ(400, page_content.width());
+  EXPECT_EQ(1100, page_content.height());
+
+  // Both X and Y centered.
+  page_size = gfx::Size(500, 500),
+  page_content = GetCenteredPageContentRect(gfx::Size(1000, 1000), page_size,
+                                            page_content_rect);
+  EXPECT_EQ(250, page_content.x());
+  EXPECT_EQ(250, page_content.y());
+  EXPECT_EQ(400, page_content.width());
+  EXPECT_EQ(1100, page_content.height());
+}
+#endif  // defined(OS_WIN)
+
 }  // namespace printing