Use printing layout correctly for subframes

When an oopif is printed along with its parent, this frame should not
use printing layout. Instead, its size is confined by its parent. Before
this change, ShouldUsePrintingLayout() works correctly in
LocalFrame::SetPrinting() since it also checks |use_printing_layout|
variable. But ShouldUsePrintingLayout() doesn't work correctly during
layout code where it is also called to decide whether printing layout
should be applied for style etc.

This CL fixes ShouldUsePrintingLayout() to return the correct value for
all cases.

BUG=853942

Change-Id: I6cad75fd6db59d00d4c07ea8b23dbaf6a4a47afc
Reviewed-on: https://chromium-review.googlesource.com/1175404
Commit-Queue: Wei Li <weili@chromium.org>
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584319}

third_party/blink/renderer/core/exported/local_frame_client_impl.cc

@@ -1138,6 +1138,10 @@ void LocalFrameClientImpl::SetMouseCapture(bool capture) {
   web_frame_->Client()->SetMouseCapture(capture);
 }
 
+bool LocalFrameClientImpl::UsePrintingLayout() const {
+  return web_frame_->UsePrintingLayout();
+}
+
 STATIC_ASSERT_ENUM(DownloadCrossOriginRedirects::kFollow,
                    WebLocalFrameClient::CrossOriginRedirects::kFollow);
 STATIC_ASSERT_ENUM(DownloadCrossOriginRedirects::kNavigate,

third_party/blink/renderer/core/exported/local_frame_client_impl.h

@@ -287,6 +287,8 @@ class LocalFrameClientImpl final : public LocalFrameClient {
 
   void SetMouseCapture(bool capture) override;
 
+  bool UsePrintingLayout() const override;
+
  private:
   explicit LocalFrameClientImpl(WebLocalFrameImpl*);
 

third_party/blink/renderer/core/frame/local_frame.cc

@@ -603,22 +603,14 @@ scoped_refptr<InspectorTaskRunner> LocalFrame::GetInspectorTaskRunner() {
 void LocalFrame::StartPrinting(const FloatSize& page_size,
                                const FloatSize& original_page_size,
                                float maximum_shrink_ratio) {
-  SetPrinting(/*printing=*/true, /*use_printing_layout=*/true, page_size,
-              original_page_size, maximum_shrink_ratio);
-}
-
-void LocalFrame::StartPrintingWithoutPrintingLayout() {
-  SetPrinting(/*printing=*/true, /*use_printing_layout=*/false, FloatSize(),
-              FloatSize(), 0);
+  SetPrinting(true, page_size, original_page_size, maximum_shrink_ratio);
 }
 
 void LocalFrame::EndPrinting() {
-  SetPrinting(/*printing=*/false, /*use_printing_layout=*/false, FloatSize(),
-              FloatSize(), 0);
+  SetPrinting(false, FloatSize(), FloatSize(), 0);
 }
 
 void LocalFrame::SetPrinting(bool printing,
-                             bool use_printing_layout,
                              const FloatSize& page_size,
                              const FloatSize& original_page_size,
                              float maximum_shrink_ratio) {
@@ -634,7 +626,7 @@ void LocalFrame::SetPrinting(bool printing,
   if (TextAutosizer* text_autosizer = GetDocument()->GetTextAutosizer())
     text_autosizer->UpdatePageInfo();
 
-  if (use_printing_layout && ShouldUsePrintingLayout()) {
+  if (ShouldUsePrintingLayout()) {
     View()->ForceLayoutForPagination(page_size, original_page_size,
                                      maximum_shrink_ratio);
   } else {
@@ -652,7 +644,7 @@ void LocalFrame::SetPrinting(bool printing,
        child = child->Tree().NextSibling()) {
     if (child->IsLocalFrame()) {
       if (printing)
-        ToLocalFrame(child)->StartPrintingWithoutPrintingLayout();
+        ToLocalFrame(child)->StartPrinting();
       else
         ToLocalFrame(child)->EndPrinting();
     }
@@ -665,19 +657,22 @@ void LocalFrame::SetPrinting(bool printing,
 }
 
 bool LocalFrame::ShouldUsePrintingLayout() const {
+  if (!GetDocument()->Printing())
+    return false;
+
   // Only the top frame being printed should be fitted to page size.
   // Subframes should be constrained by parents only.
-  // This function considers the following three kinds of frames as top frames:
+  // This function considers the following two kinds of frames as top frames:
   // -- frame with no parent;
-  // -- frame's parent is remote frame;
   // -- frame's parent is not in printing mode.
-  // Among them, if a frame's parent is a remote frame, but in printing mode,
-  // this frame should not use printing layout either. But in that case, this
-  // frame is a local top frame, the printing must start from
-  // StartPrintingWithoutPrintingLayout() so this function won't been called.
-  return GetDocument()->Printing() &&
-         (!Tree().Parent() || !Tree().Parent()->IsLocalFrame() ||
-          !ToLocalFrame(Tree().Parent())->GetDocument()->Printing());
+  // For the second type, it is a bit complicated when its parent is a remote
+  // frame. In such case, we can not check its document or other internal
+  // status. However, if the parent is in printing mode, this frame's printing
+  // must have started with |use_printing_layout| as false in print context.
+  return !Tree().Parent() ||
+         (Tree().Parent()->IsLocalFrame() &&
+          !ToLocalFrame(Tree().Parent())->GetDocument()->Printing()) ||
+         (!Tree().Parent()->IsLocalFrame() && Client()->UsePrintingLayout());
 }
 
 FloatSize LocalFrame::ResizePageRectsKeepingRatio(

third_party/blink/renderer/core/frame/local_frame.h

@@ -207,13 +207,11 @@ class CORE_EXPORT LocalFrame final : public Frame,
 
   // Begin printing with the given page size information.
   // The frame content will fit to the page size with specified shrink ratio.
-  void StartPrinting(const FloatSize& page_size,
-                     const FloatSize& original_page_size,
-                     float maximum_shrink_ratio);
-
-  // Begin printing without changing the the frame's layout. This is used for
-  // child frames because they don't need to fit to a page size.
-  void StartPrintingWithoutPrintingLayout();
+  // If this frame doesn't need to fit into a page size, default values are
+  // used.
+  void StartPrinting(const FloatSize& page_size = FloatSize(),
+                     const FloatSize& original_page_size = FloatSize(),
+                     float maximum_shrink_ratio = 0);
 
   void EndPrinting();
   bool ShouldUsePrintingLayout() const;
@@ -402,10 +400,8 @@ class CORE_EXPORT LocalFrame final : public Frame,
   // Internal implementation for starting or ending printing.
   // |printing| is true when printing starts, false when printing ends.
   // |page_size|, |original_page_size|, and |maximum_shrink_ratio| are only
-  // meaningful when starting to print with printing layout -- both |printing|
-  // and |use_printing_layout| are true.
+  // meaningful when we should use printing layout for this frame.
   void SetPrinting(bool printing,
-                   bool use_printing_layout,
                    const FloatSize& page_size,
                    const FloatSize& original_page_size,
                    float maximum_shrink_ratio);

third_party/blink/renderer/core/frame/local_frame_client.h

@@ -438,6 +438,10 @@ class CORE_EXPORT LocalFrameClient : public FrameClient {
   }
 
   virtual void SetMouseCapture(bool) {}
+
+  // Returns whether we are associated with a print context who suggests to use
+  // printing layout.
+  virtual bool UsePrintingLayout() const { return false; }
 };
 
 }  // namespace blink

third_party/blink/renderer/core/frame/web_local_frame_impl.cc

@@ -594,6 +594,10 @@ bool WebLocalFrameImpl::IsFocused() const {
              ViewImpl()->GetPage()->GetFocusController().FocusedFrame());
 }
 
+bool WebLocalFrameImpl::UsePrintingLayout() const {
+  return print_context_ ? print_context_->use_printing_layout() : false;
+}
+
 WebSize WebLocalFrameImpl::GetScrollOffset() const {
   if (ScrollableArea* scrollable_area = LayoutViewport())
     return scrollable_area->ScrollOffsetInt();

third_party/blink/renderer/core/frame/web_local_frame_impl.h

@@ -434,6 +434,9 @@ class CORE_EXPORT WebLocalFrameImpl final
   // Returns true if the frame is focused.
   bool IsFocused() const;
 
+  // Returns true if our print context suggests using printing layout.
+  bool UsePrintingLayout() const;
+
   virtual void Trace(blink::Visitor*);
 
  private:

third_party/blink/renderer/core/page/print_context.cc

@@ -148,11 +148,6 @@ void PrintContext::BeginPrintMode(float width, float height) {
   // without going back to screen mode.
   is_printing_ = true;
 
-  if (!use_printing_layout_) {
-    frame_->StartPrintingWithoutPrintingLayout();
-    return;
-  }
-
   FloatSize original_page_size = FloatSize(width, height);
   FloatSize min_layout_size = frame_->ResizePageRectsKeepingRatio(
       original_page_size, FloatSize(width * kPrintingMinimumShrinkFactor,
@@ -326,6 +321,10 @@ void PrintContext::Trace(blink::Visitor* visitor) {
   visitor->Trace(linked_destinations_);
 }
 
+bool PrintContext::use_printing_layout() const {
+  return use_printing_layout_;
+}
+
 ScopedPrintContext::ScopedPrintContext(LocalFrame* frame)
     : context_(new PrintContext(frame, /*use_printing_layout=*/true)) {}
 

third_party/blink/renderer/core/page/print_context.h

@@ -106,6 +106,8 @@ class CORE_EXPORT PrintContext
 
   virtual void Trace(blink::Visitor*);
 
+  bool use_printing_layout() const;
+
  protected:
   friend class PrintContextTest;
 

third_party/blink/renderer/core/page/print_context_test.cc

@@ -424,7 +424,7 @@ TEST_P(PrintContextFrameTest, DISABLED_SubframePrintPageLayout) {
   EXPECT_EQ(child->OffsetWidth(), 800);
   EXPECT_EQ(target->OffsetWidth(), 800);
 
-  GetDocument().GetFrame()->StartPrintingWithoutPrintingLayout();
+  GetDocument().GetFrame()->StartPrinting();
   EXPECT_EQ(parent->OffsetWidth(), 800);
   EXPECT_EQ(child->OffsetWidth(), 800);
   EXPECT_EQ(target->OffsetWidth(), 800);