[fuchsia] Replace C-style array with std::array on Scenic commands.

Scenic functions with C-style array arguments will be removed from SDK
in favor of std::arrays. This change replaces all the C-style arrays used
in Scenic SDK functions with std::array.

Change in Fuchsia-review: https://fuchsia-review.googlesource.com/c/fuchsia/+/351051

TEST=Build on Fuchsia target; run_base_unittests

Bug: fxb/SCN-1442
Change-Id: I2f828e7217258a71267295f4b26b735d29a9b103
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1986979
Commit-Queue: Yilong Li <liyl@google.com>
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Cr-Commit-Position: refs/heads/master@{#728628}

fuchsia/engine/browser/ax_tree_converter.cc

@@ -91,10 +91,10 @@ std::vector<uint32_t> ConvertChildIds(std::vector<int32_t> ids) {
 
 fuchsia::ui::gfx::BoundingBox ConvertBoundingBox(gfx::RectF bounds) {
   fuchsia::ui::gfx::BoundingBox box;
-  float min[3] = {bounds.bottom_left().x(), bounds.bottom_left().y(), 0.0f};
-  float max[3] = {bounds.top_right().x(), bounds.top_right().y(), 0.0f};
-  box.min = scenic::NewVector3(min);
-  box.max = scenic::NewVector3(max);
+  box.min = scenic::NewVector3({bounds.bottom_left().x(),
+                                bounds.bottom_left().y(), 0.0f});
+  box.max = scenic::NewVector3({bounds.top_right().x(), bounds.top_right().y(),
+                                0.0f});
   return box;
 }
 
@@ -102,8 +102,8 @@ fuchsia::ui::gfx::BoundingBox ConvertBoundingBox(gfx::RectF bounds) {
 // subtree as an optimization to handle resizing or repositioning. This requires
 // only one node to be updated on such an event.
 fuchsia::ui::gfx::mat4 ConvertTransform(gfx::Transform* transform) {
-  float mat[16] = {};
-  transform->matrix().asColMajorf(mat);
+  std::array<float, 16> mat = {};
+  transform->matrix().asColMajorf(mat.data());
   fuchsia::ui::gfx::Matrix4Value fuchsia_transform =
       scenic::NewMatrix4Value(mat);
   return fuchsia_transform.value;

fuchsia/engine/browser/ax_tree_converter_unittest.cc

@@ -26,8 +26,8 @@ const int32_t kRectX = 1;
 const int32_t kRectY = 2;
 const int32_t kRectWidth = 7;
 const int32_t kRectHeight = 8;
-const float k4DIdentityMatrix[16] = {1, 0, 0, 0, 0, 1, 0, 0,
-                                     0, 0, 1, 0, 0, 0, 0, 1};
+const std::array<float, 16> k4DIdentityMatrix = {1, 0, 0, 0, 0, 1, 0, 0,
+                                                 0, 0, 1, 0, 0, 0, 0, 1};
 
 bool SemanticNodesAreEqual(const Node& first, const Node& second) {
   if (first.node_id() != second.node_id())
@@ -128,10 +128,8 @@ TEST_F(AXTreeConverterTest, AllFieldsSetAndEqual) {
   Attributes attributes;
   attributes.set_label(kLabel1);
   fuchsia::ui::gfx::BoundingBox box;
-  float min[3] = {kRectX, kRectY + kRectHeight, 0.0f};
-  float max[3] = {kRectHeight, kRectY, 0.0f};
-  box.min = scenic::NewVector3(min);
-  box.max = scenic::NewVector3(max);
+  box.min = scenic::NewVector3({kRectX, kRectY + kRectHeight, 0.0f});
+  box.max = scenic::NewVector3({kRectHeight, kRectY, 0.0f});
   fuchsia::ui::gfx::Matrix4Value mat =
       scenic::NewMatrix4Value(k4DIdentityMatrix);
   auto expected_node = CreateSemanticNode(
@@ -179,8 +177,8 @@ TEST_F(AXTreeConverterTest, FieldMismatch) {
   Attributes attributes;
   attributes.set_label(kLabel1);
   fuchsia::ui::gfx::BoundingBox box;
-  float min[3] = {kRectX, kRectY + kRectHeight, 0.0f};
-  float max[3] = {kRectHeight, kRectY, 0.0f};
+  std::array<float, 3> min = {kRectX, kRectY + kRectHeight, 0.0f};
+  std::array<float, 3> max = {kRectHeight, kRectY, 0.0f};
   box.min = scenic::NewVector3(min);
   box.max = scenic::NewVector3(max);
   fuchsia::ui::gfx::Matrix4Value mat =