Bug 327964 EPartService's hidePart may fail when trying to hide a shared part that's in a shared container
The placeholder retrieval code in the EPartService implementation doesn't go far down deep enough and actually stops at the shared container level. This causes the placeholder of the shared part to not be found.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
public void testSaveAll_NY_True_TT_FT() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				true, true }, new boolean[] { false, true });
	}
	public void testSaveAll_NY_True_TF_TT() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				true, false }, new boolean[] { true, true });
	}
	public void testSaveAll_NY_True_TF_TF() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				true, false }, new boolean[] { true, false });
	}
	public void testSaveAll_NY_True_TF_FT() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				true, false }, new boolean[] { false, true });
	}
	public void testSaveAll_NY_True_TF_FF() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				true, false }, new boolean[] { false, false });
	}
	public void testSaveAll_NY_True_FT_TT() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				false, true }, new boolean[] { true, true });
	}
	public void testSaveAll_NY_True_FT_TF() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {
				false, true }, new boolean[] { true, false });
	}
	public void testSaveAll_NY_True_FT_FT() {
		testSaveAll(new Save[] { Save.NO, Save.YES }, true, new boolean[] {