[ozone/linux] Enabled file contents in drag data on Linux.

Historically, there were a few discrepancies in behaviour of file
drag and drop on different platforms.  With introduction of Ozone and
implementation of X11 platform it became so complicated that a few tests
had been disabled.

The core difference between Linux and non-Linux was in how string and
URI contents are handled together.  Various Linux file managers pass
both string and URI together, for which there was a workaround in the
X11 implementation but not in Wayland one.

Another difference was that drags started in the renderer did not take
files (due to security reasons) but the non-backed data provider used
in ChromeOS and Wayland didn't recognise this scenario.

This CL unifies the behaviour on Linux platforms and makes the
non-backed data provider aware of drags originated from renderer, and
enables the tests that validate this behaviour.

Bug: 1121928, 1070483
Change-Id: If64857c60df295b37f1f5d4abe11338912134f5c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2461372Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Alexander Dunaev <adunaev@igalia.com>
Cr-Commit-Position: refs/heads/master@{#816195}

content/browser/web_contents/web_contents_view_aura.cc

@@ -153,7 +153,7 @@ class WebDragSourceAura : public NotificationObserver {
   DISALLOW_COPY_AND_ASSIGN(WebDragSourceAura);
 };
 
-#if defined(USE_X11) || defined(OS_WIN)
+#if defined(OS_LINUX) || defined(OS_WIN)
 // Fill out the OSExchangeData with a file contents, synthesizing a name if
 // necessary.
 void PrepareDragForFileContents(const DropData& drop_data,
@@ -239,15 +239,11 @@ void PrepareDragData(const DropData& drop_data,
   if (!drop_data.download_metadata.empty())
     PrepareDragForDownload(drop_data, provider, web_contents);
 #endif
-#if defined(USE_X11) || defined(OS_WIN)
-  bool should_check_file_contents = true;
-#if defined(USE_X11)
-  should_check_file_contents = !features::IsUsingOzonePlatform();
-#endif
+#if defined(OS_LINUX) || defined(OS_WIN)
   // We set the file contents before the URL because the URL also sets file
   // contents (to a .URL shortcut).  We want to prefer file content data over
   // a shortcut so we add it first.
-  if (should_check_file_contents && !drop_data.file_contents.empty())
+  if (!drop_data.file_contents.empty())
     PrepareDragForFileContents(drop_data, provider);
 #endif
   // Call SetString() before SetURL() when we actually have a custom string.

content/browser/web_contents/web_contents_view_aura_unittest.cc

@@ -35,17 +35,13 @@
 #include "ui/base/dragdrop/os_exchange_data_provider_win.h"
 #endif
 
-#if defined(USE_X11)
-#include "ui/base/ui_base_features.h"
-#endif
-
 namespace content {
 
 namespace {
 constexpr gfx::Rect kBounds = gfx::Rect(0, 0, 20, 20);
 constexpr gfx::PointF kClientPt = {5, 10};
 
-#if !defined(USE_OZONE) || defined(OS_WIN) || defined(USE_X11)
+#if defined(OS_LINUX) || defined(OS_WIN)
 constexpr gfx::PointF kScreenPt = {17, 3};
 #endif
 
@@ -204,20 +200,7 @@ TEST_F(WebContentsViewAuraTest, OccludeView) {
   EXPECT_EQ(web_contents()->GetVisibility(), Visibility::VISIBLE);
 }
 
-#if !defined(USE_OZONE) && !defined(OS_CHROMEOS)
-// TODO(crbug.com/1070483): Enable this test on Ozone.
-//
-// The expectations for the X11 implementation differ from other ones because
-// the GetString() method of the X11 data provider returns an empty string
-// if file data is also present, which is not the same for other
-// implementations.  (See the code under USE_X11 in the body of the test.)
-//
-// Ozone spawns the platform at run time, which would require this test to query
-// Ozone about the current platform, which would pull the Ozone platform as the
-// dependency here.
-//
-// Another solution could be fixing the X11 platform implementation so it
-// would behave the same way as other Ozone platforms do.
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS) || defined(OS_WIN)
 TEST_F(WebContentsViewAuraTest, DragDropFiles) {
   WebContentsViewAura* view = GetView();
   auto data = std::make_unique<ui::OSExchangeData>();
@@ -253,17 +236,14 @@ TEST_F(WebContentsViewAuraTest, DragDropFiles) {
   view->OnDragEntered(event);
   ASSERT_NE(nullptr, view->current_drop_data_);
 
-#if defined(USE_X11)
-  // By design, OSExchangeDataProviderX11::GetString returns an empty string
-  // if file data is also present.
-  if (!features::IsUsingOzonePlatform()) {
-    EXPECT_TRUE(!view->current_drop_data_->text ||
-                view->current_drop_data_->text->empty());
-  } else
+#if defined(OS_LINUX)
+  // By design, Linux implementations return an empty string if file data
+  // is also present.
+  EXPECT_TRUE(!view->current_drop_data_->text ||
+              view->current_drop_data_->text->empty());
+#else
+  EXPECT_EQ(string_data, view->current_drop_data_->text);
 #endif
-  {
-    EXPECT_EQ(string_data, view->current_drop_data_->text);
-  }
 
   std::vector<ui::FileInfo> retrieved_file_infos =
       view->current_drop_data_->filenames;
@@ -287,17 +267,14 @@ TEST_F(WebContentsViewAuraTest, DragDropFiles) {
 
   CheckDropData(view);
 
-#if defined(USE_X11)
-  // By design, OSExchangeDataProviderX11::GetString returns an empty string
-  // if file data is also present.
-  if (!features::IsUsingOzonePlatform()) {
-    EXPECT_TRUE(!drop_complete_data_->drop_data.text ||
-                drop_complete_data_->drop_data.text->empty());
-  } else
+#if defined(OS_LINUX)
+  // By design, Linux implementations returns an empty string if file data
+  // is also present.
+  EXPECT_TRUE(!drop_complete_data_->drop_data.text ||
+              drop_complete_data_->drop_data.text->empty());
+#else
+  EXPECT_EQ(string_data, drop_complete_data_->drop_data.text);
 #endif
-  {
-    EXPECT_EQ(string_data, drop_complete_data_->drop_data.text);
-  }
 
   retrieved_file_infos = drop_complete_data_->drop_data.filenames;
   ASSERT_EQ(test_file_infos.size(), retrieved_file_infos.size());
@@ -308,15 +285,10 @@ TEST_F(WebContentsViewAuraTest, DragDropFiles) {
   }
 }
 
-#endif  // !defined(USE_OZONE) && !defined(OS_CHROMEOS)
+#endif  // defined(OS_LINUX) && !defined(OS_CHROMEOS) || defined(OS_WIN)
 
-#if defined(OS_WIN) || defined(USE_X11)
+#if defined(OS_LINUX) || defined(OS_WIN)
 TEST_F(WebContentsViewAuraTest, DragDropFilesOriginateFromRenderer) {
-#if defined(USE_X11)
-  // TODO(https://crbug.com/1109695): enable for Ozone/Linux.
-  if (features::IsUsingOzonePlatform())
-    return;
-#endif
   WebContentsViewAura* view = GetView();
   auto data = std::make_unique<ui::OSExchangeData>();
 
@@ -355,9 +327,9 @@ TEST_F(WebContentsViewAuraTest, DragDropFilesOriginateFromRenderer) {
   view->OnDragEntered(event);
   ASSERT_NE(nullptr, view->current_drop_data_);
 
-#if defined(USE_X11)
-  // By design, OSExchangeDataProviderX11::GetString returns an empty string
-  // if file data is also present.
+#if defined(OS_LINUX)
+  // By design, Linux implementations return an empty string if file data
+  // is also present.
   EXPECT_TRUE(!view->current_drop_data_->text ||
               view->current_drop_data_->text->empty());
 #else
@@ -379,9 +351,9 @@ TEST_F(WebContentsViewAuraTest, DragDropFilesOriginateFromRenderer) {
 
   CheckDropData(view);
 
-#if defined(USE_X11)
-  // By design, OSExchangeDataProviderX11::GetString returns an empty string
-  // if file data is also present.
+#if defined(OS_LINUX)
+  // By design, Linux implementations returns an empty string if file data is
+  // also present.
   EXPECT_TRUE(!drop_complete_data_->drop_data.text ||
               drop_complete_data_->drop_data.text->empty());
 #else

ui/base/dragdrop/os_exchange_data_provider.h

@@ -71,7 +71,7 @@ class COMPONENT_EXPORT(UI_BASE_DATA_EXCHANGE) OSExchangeDataProvider {
   virtual bool HasFile() const = 0;
   virtual bool HasCustomFormat(const ClipboardFormatType& format) const = 0;
 
-#if defined(USE_X11) || defined(OS_WIN)
+#if defined(OS_LINUX) || defined(OS_WIN)
   virtual void SetFileContents(const base::FilePath& filename,
                                const std::string& file_contents) = 0;
 #endif

ui/base/dragdrop/os_exchange_data_provider_non_backed.cc

@@ -40,12 +40,11 @@ std::unique_ptr<OSExchangeDataProvider> OSExchangeDataProviderNonBacked::Clone()
 }
 
 void OSExchangeDataProviderNonBacked::MarkOriginatedFromRenderer() {
-  // TODO(dcheng): Currently unneeded because ChromeOS Aura correctly separates
-  // URL and filename metadata, and does not implement the DownloadURL protocol.
+  originated_from_renderer_ = true;
 }
 
 bool OSExchangeDataProviderNonBacked::DidOriginateFromRenderer() const {
-  return false;
+  return originated_from_renderer_;
 }
 
 void OSExchangeDataProviderNonBacked::SetString(const base::string16& data) {
@@ -85,6 +84,15 @@ void OSExchangeDataProviderNonBacked::SetPickledData(
 }
 
 bool OSExchangeDataProviderNonBacked::GetString(base::string16* data) const {
+#if defined(OS_LINUX)
+  if (HasFile()) {
+    // Various Linux file managers both pass a list of file:// URIs and set the
+    // string representation to the URI. We explicitly don't want to return use
+    // this representation.
+    return false;
+  }
+#endif  // defined(OS_LINUX)
+
   if ((formats_ & OSExchangeData::STRING) == 0)
     return false;
   *data = string_;
@@ -160,11 +168,11 @@ bool OSExchangeDataProviderNonBacked::HasCustomFormat(
   return base::Contains(pickle_data_, format);
 }
 
-#if defined(USE_X11)
+#if defined(OS_LINUX)
 void OSExchangeDataProviderNonBacked::SetFileContents(
     const base::FilePath& filename,
     const std::string& file_contents) {
-  NOTREACHED();
+  NOTIMPLEMENTED();
 }
 #endif
 

ui/base/dragdrop/os_exchange_data_provider_non_backed.h

@@ -9,6 +9,7 @@
 
 #include "base/component_export.h"
 #include "base/pickle.h"
+#include "build/build_config.h"
 #include "ui/base/dragdrop/file_info/file_info.h"
 #include "ui/base/dragdrop/os_exchange_data_provider.h"
 #include "ui/gfx/geometry/vector2d.h"
@@ -58,7 +59,7 @@ class COMPONENT_EXPORT(UI_BASE) OSExchangeDataProviderNonBacked
   bool HasURL(FilenameToURLPolicy policy) const override;
   bool HasFile() const override;
   bool HasCustomFormat(const ClipboardFormatType& format) const override;
-#if defined(USE_X11)
+#if defined(OS_LINUX)
   void SetFileContents(const base::FilePath& filename,
                        const std::string& file_contents) override;
 #endif
@@ -104,6 +105,8 @@ class COMPONENT_EXPORT(UI_BASE) OSExchangeDataProviderNonBacked
   // For HTML format
   base::string16 html_;
   GURL base_url_;
+
+  bool originated_from_renderer_ = false;
 };
 
 }  // namespace ui

ui/base/x/x11_os_exchange_data_provider.cc

@@ -367,7 +367,6 @@ bool XOSExchangeDataProvider::HasCustomFormat(
   return !requested_types.empty();
 }
 
-#if defined(USE_X11)
 void XOSExchangeDataProvider::SetFileContents(
     const base::FilePath& filename,
     const std::string& file_contents) {
@@ -398,7 +397,6 @@ void XOSExchangeDataProvider::SetFileContents(
              scoped_refptr<base::RefCountedMemory>(
                  base::RefCountedString::TakeString(&file_contents_copy)));
 }
-#endif
 
 void XOSExchangeDataProvider::SetHtml(const base::string16& html,
                                       const GURL& base_url) {

ui/base/x/x11_os_exchange_data_provider.h

@@ -82,10 +82,8 @@ class COMPONENT_EXPORT(UI_BASE_X) XOSExchangeDataProvider
   bool HasURL(FilenameToURLPolicy policy) const override;
   bool HasFile() const override;
   bool HasCustomFormat(const ClipboardFormatType& format) const override;
-#if defined(USE_X11)
   void SetFileContents(const base::FilePath& filename,
                        const std::string& file_contents) override;
-#endif
 
   void SetHtml(const base::string16& html, const GURL& base_url) override;
   bool GetHtml(base::string16* html, GURL* base_url) const override;