Ignoring minimum size requirements for maximized windows, full screen windows and too small screens

ash/wm/window_state.cc

Index: ash/wm/window_state.cc
diff --git a/ash/wm/window_state.cc b/ash/wm/window_state.cc
index f0bed4ba0f38d31bdabbde0bf9f6c6b1b9f646b0..7c5c1674f14b050f4593608c1fa278d72e571221 100644
--- a/ash/wm/window_state.cc
+++ b/ash/wm/window_state.cc
@@ -24,6 +24,7 @@
 #include "ui/compositor/layer_tree_owner.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/gfx/display.h"
+#include "ui/gfx/screen.h"
 #include "ui/wm/core/window_util.h"
 
 namespace ash {
@@ -357,7 +358,21 @@ void WindowState::NotifyPostStateTypeChange(
 }
 
 void WindowState::SetBoundsDirect(const gfx::Rect& bounds) {
-  BoundsSetter().SetBounds(window_, bounds);
+  gfx::Rect actual_new_bounds(bounds);
+  // Ensure we don't go smaller than our minimum bounds in "normal" window
+  // modes
+  if (window_->delegate() && !IsMaximized() && !IsFullscreen()) {
+    // Get the minimum usable size of the minimum size and the screen size.
+    gfx::Size min_size = window_->delegate()->GetMinimumSize();
+    min_size.SetToMin(gfx::Screen::GetScreenFor(
+        window_)->GetDisplayNearestWindow(window_).work_area().size());
+
+    actual_new_bounds.set_width(
+        std::max(min_size.width(), actual_new_bounds.width()));
+    actual_new_bounds.set_height(
+        std::max(min_size.height(), actual_new_bounds.height()));
+  }
+  BoundsSetter().SetBounds(window_, actual_new_bounds);
 }
 
 void WindowState::SetBoundsConstrained(const gfx::Rect& bounds) {