Modernize chrome_pdf::PaintManager.

- Initialize variables in the header; make some const.
- Use = delete.
- Remove unused Initialize().
- Use more specific DCHECKs.

Change-Id: I1a9e2a35882193d7aae216ba09803bb3f8d620ca
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2154230
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Daniel Hosseinian <dhoss@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760208}

pdf/paint_manager.cc

@@ -29,24 +29,13 @@ PaintManager::PaintManager(pp::Instance* instance,
                            bool is_always_opaque)
     : instance_(instance),
       client_(client),
-      is_always_opaque_(is_always_opaque),
-      callback_factory_(nullptr),
-      manual_callback_pending_(false),
-      flush_pending_(false),
-      flush_requested_(false),
-      has_pending_resize_(false),
-      graphics_need_to_be_bound_(false),
-      pending_device_scale_(1.0),
-      device_scale_(1.0),
-      in_paint_(false),
-      first_paint_(true),
-      view_size_changed_waiting_for_paint_(false) {
+      is_always_opaque_(is_always_opaque) {
+  DCHECK(instance_);
+  DCHECK(client_);
+
   // Set the callback object outside of the initializer list to avoid a
   // compiler warning about using "this" in an initializer list.
   callback_factory_.Initialize(this);
-
-  // You can not use a NULL client pointer.
-  DCHECK(client);
 }
 
 PaintManager::~PaintManager() = default;
@@ -86,19 +75,11 @@ pp::Size PaintManager::GetNewContextSize(const pp::Size& current_context_size,
   return result;
 }
 
-void PaintManager::Initialize(pp::Instance* instance,
-                              Client* client,
-                              bool is_always_opaque) {
-  DCHECK(!instance_ && !client_);  // Can't initialize twice.
-  instance_ = instance;
-  client_ = client;
-  is_always_opaque_ = is_always_opaque;
-}
-
 void PaintManager::SetSize(const pp::Size& new_size, float device_scale) {
   if (GetEffectiveSize() == new_size &&
-      GetEffectiveDeviceScale() == device_scale)
+      GetEffectiveDeviceScale() == device_scale) {
     return;
+  }
 
   has_pending_resize_ = true;
   pending_size_ = new_size;
@@ -306,12 +287,12 @@ void PaintManager::Flush() {
   // use one device, swap it with another, then swap it back, we won't know
   // that we've already scheduled a Flush on the first device. It's best to not
   // re-use devices in this way.
-  DCHECK(result != PP_ERROR_INPROGRESS);
+  DCHECK_NE(PP_ERROR_INPROGRESS, result);
 
   if (result == PP_OK_COMPLETIONPENDING) {
     flush_pending_ = true;
   } else {
-    DCHECK(result == PP_OK);  // Catch all other errors in debug mode.
+    DCHECK_EQ(PP_OK, result);  // Catch all other errors in debug mode.
   }
 }
 

pdf/paint_manager.h

@@ -50,6 +50,7 @@ class PaintManager {
     pp::ImageData image_data;
     bool flush_now;
   };
+
   class Client {
    public:
     // Paints the given invalid area of the plugin to the given graphics
@@ -104,7 +105,8 @@ class PaintManager {
   // You will need to call SetSize before this class will do anything. Normally
   // you do this from the ViewChanged method of your plugin instance.
   PaintManager(pp::Instance* instance, Client* client, bool is_always_opaque);
-
+  PaintManager(const PaintManager&) = delete;
+  PaintManager& operator=(const PaintManager&) = delete;
   ~PaintManager();
 
   // Returns the size of the graphics context to allocate for a given plugin
@@ -114,12 +116,6 @@ class PaintManager {
   static pp::Size GetNewContextSize(const pp::Size& current_context_size,
                                     const pp::Size& plugin_size);
 
-  // You must call this function before using if you use the 0-arg constructor.
-  // See the constructor for what these arguments mean.
-  void Initialize(pp::Instance* instance,
-                  Client* client,
-                  bool is_always_opaque);
-
   // Sets the size of the plugin. If the size is the same as the previous call,
   // this will be a NOP. If the size has changed, a new device will be
   // allocated to the given size and a paint to that device will be scheduled.
@@ -160,10 +156,6 @@ class PaintManager {
   void ClearTransform();
 
  private:
-  // Disallow copy and assign (these are unimplemented).
-  PaintManager(const PaintManager&);
-  PaintManager& operator=(const PaintManager&);
-
   // Makes sure there is a callback that will trigger a paint at a later time.
   // This will be either a Flush callback telling us we're allowed to generate
   // more data, or, if there's no flush callback pending, a manual call back
@@ -183,12 +175,12 @@ class PaintManager {
   // pending.
   void OnManualCallbackComplete(int32_t);
 
-  pp::Instance* instance_;
+  pp::Instance* const instance_;
 
   // Non-owning pointer. See the constructor.
-  Client* client_;
+  Client* const client_;
 
-  bool is_always_opaque_;
+  const bool is_always_opaque_;
 
   pp::CompletionCallbackFactory<PaintManager> callback_factory_;
 
@@ -199,28 +191,28 @@ class PaintManager {
   PaintAggregator aggregator_;
 
   // See comment for EnsureCallbackPending for more on how these work.
-  bool manual_callback_pending_;
-  bool flush_pending_;
-  bool flush_requested_;
+  bool manual_callback_pending_ = false;
+  bool flush_pending_ = false;
+  bool flush_requested_ = false;
 
   // When we get a resize, we don't bind right away (see SetSize). The
   // has_pending_resize_ tells us that we need to do a resize for the next
   // paint operation. When true, the new size is in pending_size_.
-  bool has_pending_resize_;
-  bool graphics_need_to_be_bound_;
+  bool has_pending_resize_ = false;
+  bool graphics_need_to_be_bound_ = false;
   pp::Size pending_size_;
   pp::Size plugin_size_;
-  float pending_device_scale_;
-  float device_scale_;
+  float pending_device_scale_ = 1.0f;
+  float device_scale_ = 1.0f;
 
   // True iff we're in the middle of a paint.
-  bool in_paint_;
+  bool in_paint_ = false;
 
   // True if we haven't painted the plugin viewport yet.
-  bool first_paint_;
+  bool first_paint_ = true;
 
   // True when the view size just changed and we're waiting for a paint.
-  bool view_size_changed_waiting_for_paint_;
+  bool view_size_changed_waiting_for_paint_ = false;
 };
 
 #endif  // PDF_PAINT_MANAGER_H_