Revert "Reland: Plumb through an api to get display cell size from brltty"

This reverts commit cfba7924.

Reason for revert:
Tests failing on the Linux ChromiumOS MSan Tests bot:

- BrailleDisplayPrivateApiTest.WriteDots
- BrailleDisplayPrivateApiTest.KeyEvents

https://ci.chromium.org/p/chromium/builders/ci/Linux%20ChromiumOS%20MSan%20Tests/19188

Original change's description:
> Reland: Plumb through an api to get display cell size from brltty
> 
> |cell_size| was not initialized during the test which expected it to be. The parameter is optional according to idl, but in this context, it probably should be initialized.
> 
> Original change
> https://chromium-review.googlesource.com/c/chromium/src/+/2206198
> 
> TBR=dtseng@chromium.org
> 
> Change-Id: I744c7b567cf2c4d27653f4368edc9c0f635d7d8d
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2207412
> Reviewed-by: David Tseng <dtseng@chromium.org>
> Commit-Queue: David Tseng <dtseng@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#769736}

TBR=dtseng@chromium.org

Change-Id: I07143ad331dcb627ddd4a768525c1caf5330a70c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2208103Reviewed-by: Thomas Lukaszewicz <tluk@chromium.org>
Commit-Queue: Thomas Lukaszewicz <tluk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#769904}

chrome/browser/extensions/api/braille_display_private/braille_controller_brlapi.cc

@@ -74,17 +74,23 @@ BrailleControllerImpl::~BrailleControllerImpl() {
 
 void BrailleControllerImpl::TryLoadLibBrlApi() {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (skip_libbrlapi_so_load_ || libbrlapi_loader_.loaded())
+  if (libbrlapi_loader_.loaded())
     return;
 
-  // This api version needs to match the one contained in
-  // third_party/libbrlapi/brlapi.h.
-  static const char* const kSupportedVersion = "libbrlapi.so.0.8";
-
-  if (!libbrlapi_loader_.Load(kSupportedVersion)) {
-    LOG(WARNING) << "Couldn't load libbrlapi(" << kSupportedVersion << ": "
-                 << strerror(errno);
+  // This list of api versions needs to contain the one used by the
+  // corresponding brltty used by Chrome OS for this version of Chrome. For
+  // example, in Chrome OS 84, we use brltty 6.1, which is using brlapi 0.8.
+  // The relevant header is checked into //third_party/libbrlapi/. Ensure to
+  // keep this list in descendning order. Note that we keep older versions so
+  // that tests will continue to work.
+  static const char* const kSupportedVersions[] = {
+      "libbrlapi.so.0.8", "libbrlapi.so.0.7", "libbrlapi.so.0.6",
+      "libbrlapi.so.0.5"};
+  for (size_t i = 0; i < base::size(kSupportedVersions); ++i) {
+    if (libbrlapi_loader_.Load(kSupportedVersions[i]))
+      return;
   }
+  LOG(WARNING) << "Couldn't load libbrlapi: " << strerror(errno);
 }
 
 std::unique_ptr<DisplayState> BrailleControllerImpl::GetDisplayState() {
@@ -101,10 +107,6 @@ std::unique_ptr<DisplayState> BrailleControllerImpl::GetDisplayState() {
       display_state->available = true;
       display_state->text_column_count.reset(new int(columns));
       display_state->text_row_count.reset(new int(rows));
-
-      unsigned int cell_size = 0;
-      connection_->GetCellSize(&cell_size);
-    display_state->cell_size.reset(new int(cell_size));
     }
   }
   return display_state;
@@ -171,7 +173,7 @@ void BrailleControllerImpl::StartConnecting() {
     return;
   started_connecting_ = true;
   TryLoadLibBrlApi();
-  if (!libbrlapi_loader_.loaded() && !skip_libbrlapi_so_load_) {
+  if (!libbrlapi_loader_.loaded()) {
     return;
   }
 
@@ -233,7 +235,7 @@ void BrailleControllerImpl::OnSocketDirChangedOnIOThread() {
 
 void BrailleControllerImpl::TryToConnect() {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  DCHECK(skip_libbrlapi_so_load_ || libbrlapi_loader_.loaded());
+  DCHECK(libbrlapi_loader_.loaded());
   connect_scheduled_ = false;
   if (!connection_.get())
     connection_ = create_brlapi_connection_function_.Run();
@@ -291,7 +293,7 @@ void BrailleControllerImpl::Disconnect() {
 
 std::unique_ptr<BrlapiConnection>
 BrailleControllerImpl::CreateBrlapiConnection() {
-  DCHECK(skip_libbrlapi_so_load_ || libbrlapi_loader_.loaded());
+  DCHECK(libbrlapi_loader_.loaded());
   return BrlapiConnection::Create(&libbrlapi_loader_);
 }
 

chrome/browser/extensions/api/braille_display_private/braille_controller_brlapi.h

@@ -83,9 +83,6 @@ class BrailleControllerImpl : public BrailleController {
   // Manipulated by the SequencedTaskRunner.
   base::FilePathWatcher file_path_watcher_;
 
-  // Set by tests to skip libbrlapi.so loading.
-  bool skip_libbrlapi_so_load_ = false;
-
   friend struct base::DefaultSingletonTraits<BrailleControllerImpl>;
 
   DISALLOW_COPY_AND_ASSIGN(BrailleControllerImpl);

chrome/browser/extensions/api/braille_display_private/braille_display_private_apitest.cc

@@ -50,7 +50,6 @@ struct MockBrlapiConnectionData {
   bool connected;
   size_t display_columns;
   size_t display_rows;
-  size_t cell_size;
   brlapi_error_t error;
   std::vector<std::string> written_content;
   // List of brlapi key codes.  A negative number makes the connection mock
@@ -126,11 +125,6 @@ class MockBrlapiConnection : public BrlapiConnection {
     }
   }
 
-  bool GetCellSize(unsigned int* cell_size) override {
-    *cell_size = data_->cell_size;
-    return true;
-  }
-
  private:
   void NotifyDataReady() {
     on_data_ready_.Run();
@@ -158,7 +152,6 @@ class BrailleDisplayPrivateApiTest : public ExtensionApiTest {
         base::Bind(
             &BrailleDisplayPrivateApiTest::CreateBrlapiConnection,
             base::Unretained(this)));
-    BrailleControllerImpl::GetInstance()->skip_libbrlapi_so_load_ = true;
     DisableAccessibilityManagerBraille();
   }
 
@@ -266,7 +259,6 @@ IN_PROC_BROWSER_TEST_F(BrailleDisplayPrivateApiTest, KeyEvents) {
 IN_PROC_BROWSER_TEST_F(BrailleDisplayPrivateApiTest, DisplayStateChanges) {
   connection_data_.display_columns = 11;
   connection_data_.display_rows = 1;
-  connection_data_.cell_size = 6;
   connection_data_.pending_keys.push_back(kErrorKeyCode);
   connection_data_.reappear_on_disconnect = true;
   ASSERT_TRUE(RunComponentExtensionTest(

chrome/browser/extensions/api/braille_display_private/brlapi_connection.cc

@@ -44,7 +44,6 @@ class BrlapiConnectionImpl : public BrlapiConnection {
   bool GetDisplaySize(unsigned int* rows, unsigned int* columns) override;
   bool WriteDots(const std::vector<unsigned char>& cells) override;
   int ReadKey(brlapi_keyCode_t* keyCode) override;
-  bool GetCellSize(unsigned int* cell_size) override;
 
  private:
   bool CheckConnected();
@@ -181,23 +180,6 @@ int BrlapiConnectionImpl::ReadKey(brlapi_keyCode_t* key_code) {
       handle_.get(), 0 /*wait*/, key_code);
 }
 
-bool BrlapiConnectionImpl::GetCellSize(unsigned int* cell_size) {
-  if (!CheckConnected()) {
-    return false;
-  }
-
-  brlapi_param_deviceCellSize_t device_cell_size;
-  ssize_t result = libbrlapi_loader_->brlapi__getParameter(
-      handle_.get(), BRLAPI_PARAM_DEVICE_CELL_SIZE, 0, BRLAPI_PARAMF_GLOBAL,
-      &device_cell_size, sizeof(device_cell_size));
-
-  if (result == -1 || result != sizeof(device_cell_size))
-    return false;
-
-  *cell_size = device_cell_size;
-  return true;
-}
-
 bool BrlapiConnectionImpl::CheckConnected() {
   if (!handle_) {
     BrlapiError()->brlerrno = BRLAPI_ERROR_ILLEGAL_INSTRUCTION;

chrome/browser/extensions/api/braille_display_private/brlapi_connection.h

@@ -67,9 +67,6 @@ class BrlapiConnection {
   // value.
   virtual int ReadKey(brlapi_keyCode_t* keyCode) = 0;
 
-  // Gets the number of dots in a braille cell.
-  virtual bool GetCellSize(unsigned int* cell_size) = 0;
-
  protected:
   BrlapiConnection();
   DISALLOW_COPY_AND_ASSIGN(BrlapiConnection);

chrome/common/extensions/api/braille_display_private.idl

@@ -56,8 +56,6 @@ namespace brailleDisplayPrivate {
     long? textRowCount;
     // Number of columns of braille cells on the currently connected display.
     long? textColumnCount;
-    // The number of dots in a braille cell on the currently connected display.
-    long? cellSize;
   };
 
   callback DisplayStateCallback = void(DisplayState result);

chrome/test/data/extensions/api_test/braille_display_private/display_state_changes/test.js

@@ -9,9 +9,9 @@ var pass = chrome.test.callbackPass;
 
 var callbackCompleted;
 var EXPECTED_EVENTS = [
-  {'available': true, 'textColumnCount': 11, 'textRowCount': 1, cellSize: 6},
-  {'available': false},
-  {'available': true, 'textColumnCount': 22, 'textRowCount': 1, cellSize: 6},
+  { "available": true, "textColumnCount": 11, "textRowCount": 1 },
+  { "available": false },
+  { "available": true, "textColumnCount": 22, "textRowCount": 1 },
 ];
 
 var eventNumber = 0;

third_party/libbrlapi/BUILD.gn

@@ -23,6 +23,5 @@ generate_library_loader("libbrlapi") {
     "brlapi__leaveTtyMode",
     "brlapi__writeDots",
     "brlapi__readKey",
-    "brlapi__getParameter",
   ]
 }