tdf#96536 sw Hide Whitespace: shrink oversized page frames on para delete

The body frame did get a request to shrink, but because it had fixed
size, nothing happened. Trigger a recalc that does the right thing wrt.
hidden whitespace.

(cherry picked from commit 72f00672)

Conflicts:
	sw/qa/extras/uiwriter/uiwriter.cxx
	sw/source/core/layout/calcmove.cxx

Change-Id: I446978da8b33372c2ab30200b45b1bcec1dea7a0

sw/qa/extras/uiwriter/uiwriter.cxx

@@ -106,6 +106,7 @@ public:
     void testTdf89954();
     void testTdf89720();
     void testTdf96515();
+    void testTdf96536();
 
     CPPUNIT_TEST_SUITE(SwUiWriterTest);
     CPPUNIT_TEST(testReplaceForward);
@@ -149,6 +150,7 @@ public:
     CPPUNIT_TEST(testTdf89954);
     CPPUNIT_TEST(testTdf89720);
     CPPUNIT_TEST(testTdf96515);
+    CPPUNIT_TEST(testTdf96536);
 
     CPPUNIT_TEST_SUITE_END();
 
@@ -1172,6 +1174,29 @@ void SwUiWriterTest::testTdf96515()
     CPPUNIT_ASSERT_EQUAL(1, getPages());
 }
 
+void SwUiWriterTest::testTdf96536()
+{
+    // Enable hide whitespace mode.
+    SwDoc* pDoc = createDoc();
+    SwWrtShell* pWrtShell = pDoc->GetDocShell()->GetWrtShell();
+    SwViewOption aViewOptions(*pWrtShell->GetViewOptions());
+    aViewOptions.SetHideWhitespaceMode(true);
+    pWrtShell->ApplyViewOptions(aViewOptions);
+
+    // Insert a new paragraph at the end of the document, and then delete it.
+    uno::Reference<text::XTextDocument> xTextDocument(mxComponent, uno::UNO_QUERY);
+    uno::Reference<text::XParagraphAppend> xParagraphAppend(xTextDocument->getText(), uno::UNO_QUERY);
+    xParagraphAppend->finishParagraph(uno::Sequence<beans::PropertyValue>());
+    calcLayout();
+    uno::Reference<lang::XComponent> xParagraph(getParagraph(2), uno::UNO_QUERY);
+    xParagraph->dispose();
+    calcLayout();
+
+    // This was 552, page did not shrink after deleting the second paragraph.
+    // 276 is 12pt font size + default line spacing (15%).
+    CPPUNIT_ASSERT_EQUAL(static_cast<sal_Int32>(276), parseDump("/root/infos/bounds", "height").toInt32());
+}
+
 CPPUNIT_TEST_SUITE_REGISTRATION(SwUiWriterTest);
 CPPUNIT_PLUGIN_IMPLEMENT();
 

sw/source/core/layout/calcmove.cxx

@@ -1521,7 +1521,8 @@ void SwContentFrm::MakeAll(vcl::RenderContext* /*pRenderContext*/)
         const long nPrtBottom = (GetUpper()->*fnRect->fnGetPrtBottom)();
         long nBottomDist =  (Frm().*fnRect->fnBottomDist)( nPrtBottom );
 
-        if (getRootFrm()->GetCurrShell()->GetViewOptions()->IsWhitespaceHidden())
+        SwViewShell* pShell = getRootFrm()->GetCurrShell();
+        if (pShell && pShell->GetViewOptions()->IsWhitespaceHidden())
         {
             // When whitespace is hidden, the page frame has two heights: the
             // nominal (defined by the frame format), and the actual (which is

sw/source/core/layout/wsfrm.cxx

@@ -2358,6 +2358,21 @@ SwTwips SwLayoutFrm::ShrinkFrm( SwTwips nDist, bool bTst, bool bInfo )
     const SwViewShell *pSh = getRootFrm()->GetCurrShell();
     const bool bBrowse = pSh && pSh->GetViewOptions()->getBrowseMode();
     const sal_uInt16 nTmpType = bBrowse ? 0x2084: 0x2004; //Row+Cell, Browse by Body.
+
+    if (pSh && pSh->GetViewOptions()->IsWhitespaceHidden())
+    {
+        if (IsBodyFrm())
+        {
+            // Whitespace is hidden and this body frame will not shrink, as it
+            // has a fix size.
+            // Invalidate the page frame size, so in case the reason for the
+            // shrink was that there is more whitespace on this page, the size
+            // without whitespace will be recalculated correctly.
+            SwPageFrm* pPageFrame = FindPageFrm();
+            pPageFrame->InvalidateSize();
+        }
+    }
+
     if( !(GetType() & nTmpType) && HasFixSize() )
         return 0;