Don't try to modify PIP window size upon work area change.

This handles the case where the client changes the size of the PIP
window after restore-bounds are saved for it. We just want to restore
the position, not the size after, for example, showing and hiding the
virtual keyboard.

Bug: b/129385430
Test: added unit test
Change-Id: If34134a69b4ea9698b302de10c6a1d8371e9ecaf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1547612
Commit-Queue: Eliot Courtney <edcourtney@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#647090}

ash/wm/pip/pip_positioner.cc

@@ -278,10 +278,13 @@ gfx::Rect PipPositioner::GetPositionAfterMovementAreaChange(
   // Restore to previous bounds if we have them. This lets us move the PIP
   // window back to its original bounds after transient movement area changes,
   // like the keyboard popping up and pushing the PIP window up.
-  const gfx::Rect bounds_in_screen =
-      window_state->HasRestoreBounds()
-          ? window_state->GetRestoreBoundsInScreen()
-          : window_state->window()->GetBoundsInScreen();
+  gfx::Rect bounds_in_screen = window_state->window()->GetBoundsInScreen();
+  // If the client changes the window size, don't try to resize it back for
+  // restore.
+  if (window_state->HasRestoreBounds()) {
+    bounds_in_screen.set_origin(
+        window_state->GetRestoreBoundsInScreen().origin());
+  }
   return GetRestingPosition(window_state->GetDisplay(), bounds_in_screen);
 }
 

ash/wm/pip/pip_unittest.cc

@@ -246,4 +246,30 @@ TEST_F(
   EXPECT_EQ(gfx::Rect(408, 292, 100, 100), window->GetBoundsInScreen());
 }
 
+TEST_F(PipTest, PipRestoreOnWorkAreaChangeDoesNotChangeWindowSize) {
+  ForceHideShelvesForTest();
+  UpdateDisplay("400x400");
+  std::unique_ptr<aura::Window> window(
+      CreateTestWindowInShellWithBounds(gfx::Rect(200, 200, 100, 100)));
+  wm::WindowState* window_state = wm::GetWindowState(window.get());
+  const wm::WMEvent enter_pip(wm::WM_EVENT_PIP);
+  window_state->OnWMEvent(&enter_pip);
+  window->Show();
+
+  // Position the PIP window on the side of the screen where it will be next
+  // to an edge and therefore in a resting position for the whole test.
+  const gfx::Rect bounds = gfx::Rect(292, 200, 100, 100);
+  window->SetBounds(bounds);
+  // Set the restore bounds to be a different size.
+  window_state->SetRestoreBoundsInParent(gfx::Rect(342, 250, 50, 100));
+  EXPECT_TRUE(window_state->HasRestoreBounds());
+
+  // Update the work area so that the PIP window should be pushed upward.
+  UpdateDisplay("400x200");
+  ForceHideShelvesForTest();
+
+  // The PIP window should not change size.
+  EXPECT_EQ(gfx::Rect(292, 92, 100, 100), window->GetBoundsInScreen());
+}
+
 }  // namespace ash